Never underestimate the network effect. That's probably the #1 selling point of Bitcoin. Everyone in the cryptocurrency scene can accept and send bitcoins. It's used as the gateway to and from fiat for quite many.

I like to compare Bitcoin with IRC. Back in the 90s, everyone that was chatting on the Internet would be connected to the IRC network. In 1996 the network was efficiently split in two parts due to disagreements on the obscure details of protocol development - and I'm quite sure that of all those remembering the split, very few remembers what the argument was all about. The split followed geographical borders pretty much - making it very clear that the very most of the irc server administrators didn't really look objectively into the arguments and technicalities and made up their own mind - that's just what we're seeing with Bitcoin too, I believe most big-blockers and small-blockers haven't really tried hard to make up their own mind based on the technical arguments and objective facts, they just happen to trust and believe in some people, while distrusting the others.

The utility value of IRC fell when users experienced that some of their chat-friends ended up at the wrong side of the fork.

In 1996, ICQ also appeared. Compared to IRC, I think it was quite retarded - i.e. no group chat, just person-to-person-chat, users identified by numbers instead of easy-to-remember nicks, and worst of all - it was a centralized, closed commercial silo. I experienced that quite many of my IRC-friends stopped being on IRC, they told me to install ICQ to get in touch with them. I won't say that the network split was the only reason, but I believe it was a major part of the reason why people went to ICQ instead.

In absolute numbers of users, IRC probably peaked around 2003 - but as for the percentage of the internet population being connected, it probably peaked in 1996. ICQ outpaced IRC very quickly.

Where is IRC today? Well, I do use it, and I'm not the only one ... but I do admit it is indeed quite bad, very little protocol development since 1996, quite bad security-wise, and quite many bad design-choices. Unfortunately the alternative to IRC has become a jungle of alternative chat-platforms, most of them commercial centralized closed-down silos, some few alternatives based on open source and open standards.

Anything Bitcoin can do, some alt-coin can do better - the problem is just that if Bitcoin would fail (arguably, for the payment usecase - the very usecase bitcoin was supposed to fill - Bitcoin has already failed), there would not be one alt-coin to fill the vacuum, there is indeed a jungle of them, there wouldn't be any universal agreements on "let's use this one" ...