I used to like bootstrap. Still do. But it has some faults… Depending on your needs you’re loading a lot of CSS you aren’t using.
Bootstrap 5.3 is 59kb before gzip. 6700 lines of code. That’s a lot to just apply some simple styles.
There are a ton of lighter weight alternatives nowadays.
That could be avoided by using on prem properly, too. People are very capable of making bad infrastructure whether on prem or cloud.