Earlier quoted context omitted.
>>> I don't care where you land on the side of the debate whether to use Bootstrap or not. I used to be totally against Bootstrap for a myriad of reasons. Then I got hired to build a fairly complex transactional application for a large health care organization under a tight schedule. Bootstrap allowed me to get a UI up and running super fast with all the components I needed, out of the box. It literally saved me hund…
I never got the hate for Boostrap or other frameworks. They definitely save a lot of time, and you don't necessarily end up looking like every other site if you put in some effort[1]. [1] http://expo.getbootstrap.com/
Properly theming (at least in 3.x) took a lot of effort. Just try to make a theme whereby at first glance, you can't tell that Bootstrap was used. It's not that it's not possible to do, it just took a lot of time and effort to nitpick over every detail.
In professional environments (ie: real flesh and blood companies), developers cannot say "we're using Bootstrap's default theme". The business has designers, the designers come up with a design, and unless the developer can customize Bootstrap to accommodate the requirements, in a reasonable amount of time to meet deadlines, Bootstrap is simply not an option outside of using the grid system.