All of the reasons you mentioned here are reasons why Juneau’s importance in Alaska has declined, largely in favor of Anchorage, in the past several decades. Juneau’s status as capital is a relic of Alaska’s past, before Prudhoe Bay became one of the largest and most economically significant oil fields in the world and Bering Sea fisheries became a major source of crab and fish exports, when the bulk of Alaska was almost entirely devoid of American settlement and the southeastern Alexander Archipelago was the state's population center.

Starting around 1810 and lasting until the mid 1890s, Sitka was the largest European settlement in Alaska. Sitka is fairly near Juneau and suffers from most of the same problems as the current capital. However, it lies directly on the Pacific Coast, making it a critical waypoint on ships traveling between the American West Coast and the rest of Alaska. Additionally, the area surrounding it is rich in fish and whales, and it remains a major fishing hub today. Being located near to native Tlingit lands, Sitka also served as the easternmost hub of the sprawling Russian fur trade. These two aspects made Sitka grow more rapidly than most other Russian settlements, and it was made capital of Russian Alaska in 1808. It remained the capital of American Alaska until 1906.

Juneau is several decades younger. Though similarly valuable for salmon fishing, it was far less convenient to reach, being located deep inside the Alexander Archipelago and thus harder to access by sea. It received little attention from European explorers and fishers as much more convenient locations were available, but the discovery of Gold in 1880 led to its almost instantaneous settlement. Juneau emerged as a colony of mixed American, Russian, and Tlingit ancestry, and was the capital of the Alaskan Gold Mines long before it was the capital of Alaska itself.

The Juneau mines were dwarfed by the Klondike mines that soon followed. In 1896, deep in the Canadian territory of Yukon just east of Alaska, massive gold deposits were discovered that led both Canadian and American immigrants to the region en masse. The Klondike Gold Rush arguably created modern Alaska, as an influx of American settlers doubled the territory’s population and shifted the culture of the territory from its Russian roots to its distinctly American modern character. The Skagway Route was the most utilized path from the continent to Yukon owing to its somewhat low cost, and it took prospectors straight past (and sometimes into) Juneau. Juneau became critical in coordinating communications and trade between the Yukon prospectors and America as a whole. The population of Juneau boomed while Sitka declined, and in 1906 it was made Capital of Alaska.

Even in 1906, Juneau had lost much of its gold-rush importance. The American economy had recovered from the Depression of 1897, while the 1899 discovery of gold in the Seward Peninsula (western Alaska) and 1901 discovery of gold near Fairbanks (central Alaska) attracted many miners who would otherwise have gone to Yukon. Profits declined as the most accessible gold reserves were depleted, and by 1905 the flood of prospectors had slowed to a few drops. Accordingly, Juneau’s population dropped, but it had still fully eclipsed Sitka in importance and was by far Alaska’s most populous settlement (1644 people vs. Sitka’s 1035 in the 1910 census).

Anchorage is even younger than Juneau. Its geographical position is roughly in the center of the Alaskan Coast near the mouths of the Susitna and Matanuska rivers. This is a decent enough position to encourage a settlement alone, but more importantly, the then-tiny settlement of Anchorage was chosen as a station along the Alaska Railway—built between 1903 and 1923 to connect Fairbanks (at this point Alaska’s largest gold mining city) to the coastline. Anchorage was essentially THE transportation hub for most of Alaska from this point on, and it became the site of one of Alaska’s first airports in 1930, and was the end point of the Alaska Highway (completed in 1942). Anchorage’s role as a central trading hub (replacing Juneau) led to gradual population growth. By the time of the 1950 census, it had became Alaska’s largest city.

With the Alaskan Oil Rush of the 1970s and 80s Anchorage became even more important in connecting Prudhoe Bay to the rest of the continent. Between 1970 and 1990, the population of Anchorage rose from 48,081 to 226,338. In the same time frame, the population of Juneau only rose from 6,050 to 26,751. While both were greatly expanded by the Oil Rush, Juneau was still dwarfed by comparison. Even still, Juneau and Sitka remain important, being the third and fourth largest settlements in Alaska respectively (Fairbanks places second, Anchorage is first).

While it makes sense to argue that based on Anchorage’s newfound importance, that it would be the most logical capital placement (many Alaskans would agree with you), the process of moving the capital from Juneau to Anchorage would be expensive, time consuming, and difficult. This, coupled with intense lobbying from citizens of Juneau itself, has made efforts (of which there have been many) to move the capital effectively impossible. Whether it should be moved or not is a messy political question of a state I’ve never even set foot in, so I can’t comment on the nature or merits of the debate beyond that.