For one thing, they're stable, have consistent progress between releases, don't take eons between releases, and provide pretty much the exact same functionality.
Perhaps the implementation is no better (since it's all just relatively simple CSS), but having timely releases is a big plus in my opinion, something which TB4 has failed to deliver for what, over two years now?
Why not just use flexboxgrid and throw a few quick base classes for buttons and whatnot together? It's smaller in size and provides equal grid functionality, which is really the primary value of CSS frameworks anyway.
We get it. You don't like Bootstrap. I love it, use it all the time, and am grateful for all the effort the developers are putting into it. Sure, I'd love v4 to be released more quickly, but since I have contributed nothing to it, I can't moan about how long it's taking.
Perhaps the implementation is no better (since it's all just relatively simple CSS), but having timely releases is a big plus in my opinion, something which TB4 has failed to deliver for what, over two years now?
Why not just use flexboxgrid and throw a few quick base classes for buttons and whatnot together? It's smaller in size and provides equal grid functionality, which is really the primary value of CSS frameworks anyway.