I used to think bootstrap was bloated too...and then i had heard - now, i don't know if its true - that bootstrap was originally intended *ONLY* as an internal prototype building tool, and any bloat did not matter...because expected audience, usage would be totally fine for a bloated framework...When i heard, i gave boostrap more of a pass...but, then again, i stopped using it, and began using other, lighter weight frameworks...and nowadays, i so rarely touch any web stuff...and when i do its only for me so then use zero frameworks, and merely display whatever default the browser shows with zero CSS, javascript...then again, my private web page needs are so basic anyway.
The problem with Bootstrap is that it depends on jQuery and Popper, and its CSS has global classes. It’s perfectly fine if BS is the only UI framework, but if you need to bring to bring in other frameworks or libraries (by choice or by force), then there’s a chance you’ll run into conflicts.
bootstrap has not depended on jquery for a long time now.
Unless you’re stuck on an older version. Also there is a jQuery resolver still embedded even in the latest version that looks for jQuery and tries to use it if it’s globally defined. Caused some nasty bugs in certain Enterprise applications and I have had to manually gut this from the official release.