Several days ago I read about new Bootstrap version 5, for now only as alpha. I got to say I didn't like Bootstrap, it contains a lot of stuff that you simply won't need. And another thing is in most cases you get some specific design that you need to follow which leads to replacing and reseting a lot of Bootstrap styles and that's just not the way you want to write CSS, well you certainly shouldn't.
But since Bootstrap has moved to SASS and now in version 5 has dropped jQuery, it looks quite alright. Also new breakpoint has been added, that was truly needed as well. Those are certainly changes I welcome. Bootstrap has matured and I suppose I will not be concerned anymore when client wants me to use it .