Tailwind is bound to succeed, because JavaScript and JSON succeeded, and so did yaml. The core logic is:
People like things that are simple to the point of being stupid, myself included.
Yep! I was a heavy Bootstrap user for many years, along with all the fun of maintaining sprawling trees of SASS files, imports, utility functions etc.
I hemmed and hawed when I first had to learn Tailwind - “what are these classes? How does that work? Excuse me what?” But honestly it took very little time to get the hang of it, and with the Tailwind LSP it’s so simple that it seems like using anything else would be annoying at best.