Capitalism is notoriously difficult to define, and till this day historians debate not only what it is exactly but also when it started. While some consider capitalism as we know it to only have started in Great Britain after the 18th century Enclosure Movement, others find its source in the economies of Italian city states in the Late Middle Ages. Now I definitely can't claim to have a final say in this, but I personally believe Columbus himself shouldn't be viewed as a capitalist despite the fact that he would play a big part in its origins through his discovery.

Personally I'm a fan of Bas Van Bavel's concept of factor markets to understand capitalism, which he sees as societies where land, labor and capital are mostly allocated through a market mechanism instead of traditional mechanisms. While for example land in a feudal society is tied to hereditary rights, a factor market allows people to exchange land in exchange for a currency. The same goes for labor, which went from being based on slavery or serfdom to wage labor, or capital which became increasingly available to 'common folk' (i.e. any non-noble with money to spend) through the growth of banks and credit.

Now I'm completely oversimplifying a lot here, but perfect capitalism as Adam Smith would see it means complete liberty for people to participate in these markets, which would in turn benefit every participant. Of course Marx would then argue that there's no such thing as liberty if you're being forced to sell your labor to participate in the market but that's a completely different discussion of course. For the sake of simplicity I will stick to Van Bavel's definition as I go into why I don't believe Columbus is capitalist.

Now as I said late medieval Italy has often been viewed as at the very least proto-capitalist. It makes sense: especially the north of the country was very urbanised. These cities managed to distance themselves from feudal rule. They became a haven for trade with the Near East, leading to large capitals accruing and the foundation of banks to bring this capital in motion. As their ships grew larger, so too did the financial engineering that made them profitable. Shares allowed the pooling of capital to fund these risky endeavors while minimizing potential losses. There was definitely the classically capitalist mindset of infinite growth as each city tried to secure as many trade monopolies as it could.

Columbus was Genovese himself but the voyage that made him famous was sponsored by the Spanish. Contrary to Italy, Spain can hardly be considered proto-capitalist. Feudalism was still the name of the game there, which partly explains why his trip to the Americas was in name of the Spanish crown: they were the monarchs so they had the capital to fund such a trip simply due to the families they were born into. When Columbus started colonizing the Americas, it was to further the agenda of the Spanish crown and not the market.

This would live on in the Spanish colonial system, which was basically an exported version of Spanish feudalism. Encomiendas weren't capitalist in nature if we follow Van Bavel's reasoning, since they were in essence the property of the crown that was being 'leased'. There was no market to invest in the colonies, you basically just had to be a nobleman and get close to the king and hope for the best. The natives became forced laborers tied to the owners of the land. Columbus himself didn't formally set up this system but he did set the foundation through his subjugation of the indigenous.

That being said, the discovery of the colonies would mean a huge boom to the origins of capitalism as we know it today in the long run. Especially the Dutch would run with the huge increase that there suddenly was in the market. Just like with the Italians before them, the 17th century in Holland saw a huge increase in the importance of markets for land, labor and capital. Investments and insurances allowed for risky ventures intercontinental ventures in a way that would benefit any person with the means to invest instead of only those with fancy titles. And of course they would be followed by the British soon after who would in turn be usurped by their own colonial experiment, America, the Mecca of capitalism. Now there's a lot more to be said of course about the interactions between colonialism and capitalism (and slavery for that matter) but I feel this answer has gotten long enough.

Suffice to say the earliest capitalist powers would never have been able to grow the way they did without colonial Spain paving the way with their extraction economics, but because the Spanish stuck to their feudal ways instead of letting the market dictate the allocation of land, labor and capital, I believe Spain in the 15th century, and by extension Columbus, shouldn't be viewed as capitalist.