I believe that bitcoin supremacy is not threatened, not in any significant way. Probably the main challenge is to identify where the strength of Bitcoin lies. And the obvious, or not so obvious answer is in the Bitcoin network and the people taking care of it. Look at its hash power, its stability, its uninterrupted operation.
Contrary to one may believe initially, Bitcoin's main strength is not in the code. Because the code is open source. Anyone can copy the code, change one or two things, and proclaim new coins. This we have seen in the past numerous times, starting with Litecoin, and so on.
I struggle with direct comparison of some coins. Those largely based on the original BTC code (BCH, LTC) are rather easy to compare,
Sure, they are easy to compare because they are just a copy of BTC with minor modifications. But again, they don't have the strength of the Bitcoin network and its developers.
but with some, I struggle (EOS, IOTA).
They cannot really be compared, because their
modus operandi is different. They have traded the decentralized, distributed features of bitcoin for a more centralized solution with increased transaction speed. But then again, we already have Visa if we want high throughput and high degree of centralization.
It’s pretty interesting to read the whitepapers (although it takes time as I study finance and not computer science...) but I can’t believe that there isn’t any material or comprehensive list out there where people compared the coins in terms of capabilities, speed and so on and did what I’m doing right now.
I haven't seen any that will contain a significant number of coins. There are lists, or something like infographics comparing 2,3, or several at the time. So when you have successfully compiled this list, don't forget to share it here.