Nice article. I think it is more along the lines of them wanting to stick only with the most reputable coins. I do not think twitter will eventually add support for 50+ coins, I think its going to stick to only a few. Jack Dorsey is a huge BTC supporter, and most BTC supporters also support ETH and XMR, but for the more hardcore supporters, thats about it, usually their support is only concentrated in the top few trustworthy coins. And BTC is both so widely supported and so cheap to send the last couple years that there is not really an urgent need to add another coin for donations. The most expensive BTC transaction I made in the past 2 years over 40+ transactions was $0.60, with the average price being $0.20, and often I could even send for 1 sat for $0.09 - $0.12.
But we will see. I do think they want to learn toward keeping it more simple though, and BTC, ETH, and NFTs support is a lot already to add feature wise in a relatively short period of time.