Some traditional foods are very old, some probably over 10,000 years old. Some "traditional" foods are very young, either having recently changed from an older form, or only having become common recently.

What foods are very old? Flatbreads similar to some modern flatbreads appear to predate agriculture (which IMO should be unsurprising, because pre-existing use of cereal grains will have been an important motivation for deliberately growing it). Yoghurts and cheeses made from strained yoghurts are very old, and probably date to the earliest dairy industries. Grilled, boiled, and roasted meats are very old. Thus, dishes combining such ancient ingredients, such as flatbread with yoghurt dip or cheese, grilled meat with flatbread, etc. are very old, and are important traditional dishes in parts of the world.

Our oldest written sources about foods are from Western Asia (notably, Mesopotamia). Dishes such as pilaf cooked using bulgur/burghul are ancient. The Yale culinary tablets, a collection of Babylonian recipes from c. 1800BC, contain dishes that still fit well into the local cuisine (e.g., meat cooked with garlic, onions, and cumin).

How much did the colombian exchange changed the cuisine relief in the world.

In some places, the Columbian exchange brought new foods that were used in similar ways to earlier foods. In some cases, the new foods were grown and used alongside the old foods they partly replaced (this is a good food-security strategy for subsistence farmers). For example, in West Africa, the peanut was similar to the African bambara nut, and was used in similar ways. Cassava was used similarly to yams and Old World Taros. Today, peanut soup is a classic West African traditional dish, but is post-Columbian. However, similar soups made with bambara nuts have longer histories. Similar, cassava/manioc fufu is post-Columbian, but fufu made from yam, taro, or plantain are much older.

In other places, there were major changes due to Columbian exchange, with maize replacing wheat or barley, or potatoes replacing rye or barley, or cassava replacing old staples that were cooked differently. Where maize dishes such as polenta replaced pasta or bread, potatoes replaced bread, etc., cuisines changed a lot. Where maize porridge replaced millet porridge, changes were smaller - a major ingredient changes, but apart from that, dishes remained similar.

This question of whether new major ingredients were used similarly or differently to old major ingredients is important for how much cuisines changed. For example, while chilli-red Chinese cabbage (Brassica rapa pekinensis) kimchi is relatively new to Korea (chillies being a Columbian exchange arrival, and B. rapa pekinensis arriving in Korea even later), kimchi in general is a very old Korean tradition (and water-kimchi made with radish is an example of a very old style of kimchi). Tomatoes, chillies, and potatoes are common in Indian cooking, and all are Columbian exchange foods. However, many Indian dishes that don't use these ingredients are Medieval in style, or older.

In some cases, there are recent changes in cooking styles that have made some foods quite common - some of these are regarded as "traditional" even if they are very recent. Japanese cuisine has many examples of foods that only developed after the Meiji Restoration that are considered traditional. This included dishes such as Japanese curry, and many meat dishes, and many fried dishes - frying as part of everyday cooking is a new introduction to Korea and Japan (the Columbian exchange similarly brought frying in oil/fat to the Americas).

In some cases, economic growth has made dishes that were previously out of reach of all but the elites accessible to all. For example, much of what is on the usual Korean restaurant menu outside Korea would have been unimaginable for most Koreans as recently as the 1950s - meat consumption per capita has grown by more than a factor of 10 since then, and the "beef = traditional Korean" is a modernism. The heavy use of sugar in modern Korean restaurant food (and modern Korean home cooking) is also a purely modern development.

Do recent origins invalidate claims of "traditional". I see no reason why they should. Cuisine changes, and traditions change. Some traditional dishes are very recent, such as the already-mentioned Japanese curry. That great British classic, fish and chips, is a mid-19th century development. One classic traditional Korean dish, "army-base stew/soup", developed during the Korean War. This dishes all have clear national links, and are distinct from dishes they might have developed from.

Is there some country that were mostly unaffected by all the new goods or the globalization did his job and altered the inside out of food culture everywhere.

Much central Eurasian food (including Central Asian, Iranian, Afghan, Armenian food) has been little affected by the Columbian exchange. Where Columbian exchange foods are used, they are often used in pre-Columbian styles (e.g., kidney beans replaced Old World beans). This region was the meeting place of foods from across Europe and Asia, and was not suitable for tropical New World Crops. The main New World influences were new beans becoming available, some new vegetables such as tomatoes and pumpkins, and chillies. The major New World food that resulted in quite different dishes was maize, but wheat and rice remain common - they haven't been displaced by maize.

Perhaps the largest changes have taken place on some Pacific islands. This is mostly not due to the Columbian exchange as such (although cassava is often an important new food), but more generally due to the introduction of modern Western foods. Canned corned beef, mutton/beef flaps (i.e., fatty belly meat), sugar, fluffy white bread, canned condensed milk have become popular. So large have the changes in cuisine been that some (too many!) islands have diabetes rates over 10%, with some over 20%, and many have obesity rates of over 40%.

For example, at least 2/3 of this list of 15 traditional Tongan dishes is of recent origin: https://www.nomlist.com/15-tongan-foods-you-must-try/