It's not just fashion. It's a question of "Do I want someone to use my software?", because with GPL the answer would be no for a lot of projects.
That's what GPL ensures. You can use GPL software anywhere but if you're giving it to other people, you have to give them the same rights you were afforded. And sometimes that also means giving them access to your software too.
LGPL exists too. Makes it a bit more simple for drop-in-libraries.
I find the entitlement complex that some software developers have over other peoples' software to be bizarre. "How dare you offer this free software under terms that don't allow me to exploit your labor commercially without the slightest contribution!" is a real thing that real people say every goddamn time you dare release anything not MIT/BSD licensed.
As discussed upthread, avoiding being used in closed source projects is the entire purpose of the GPL.
You can of course compose your system of closed-source and GPL'd parts, as long as GPL'd parts are separate, and remain open.
And I'm not arguing for people to not use GPL. All I'm saying is there are valid reasons to use MIT (or whatever) if ones goal is to make their project as usable as possible.
It takes a very forward-thinking person to understand that they have more to gain from the thousands of eyes and the support of the community, than from a paywall that gates access to their creation. (And that person could reasonably choose to license their software as GPL or any other open license, there are lots of trade-offs.)
But if you're not building the system from scratch, you need to be aware of the licenses you've accepted, and for many businesses the addition of GPL software to the stack will be a non-starter. Do you think we'd have Apple as it is today if it wasn't for BSD Unix and the BSD license?
But indeed, GPL does limit the ways you can distribute software licensed under it. In particular, licensing something like a library, or another early-bound component under GPL forces the users to license their work under GPL, too. This is why LGPL exists.
It's simply wrong to say that nobody pays attention to this. It's a choice you make, and whether you view the consequences as "repercussions" or "features" depends entirely on your view and the actual outcomes of those choices.
Fwiw I understand that Darwin is also available as BSD, so it seems you can get some good actors that are willing to pay it forward without necessarily needing to add a license that goads them into it.
Their subsequent choice to use BSD-licensed components, and to support/create BSD-licensed components where only GPLed components existed, must be seen in the light of this experience.
(If they have a good legal department that understands intellectual property issues at all, and their product team knows they don't actually need to hack on the Linux kernel to make whatever they're building, then they will not likely be restricted against using Linux ... but the decision will necessarily restrict their choices when finding other components to use as part of the system they are building.)
Whether that is a good thing or a bad thing, I certainly feel is debatable and I'll reserve judgement. But it is provably wrong to say that nobody chooses not to use a GPL-licensed piece of software because of the license it is distributed under. Tons of people do.
GPL licensing will not stop me from using your software. It will stop some people. I do not say that I agree with those people and their decisions. I could not have built my career without GPL software, and it does not stop me.
GPL is unpopular, and if you want people to use your software, it is the wrong license to choose.
Should it be? Perhaps not. ...but I don't think the parent comment is nearly as wrong as people seem to think.
It doesn't matter if the GPL technically is a better or worse license; the fact is that (perhaps indeed driven by large corporations) GPL has a very negative image right now, and since we do live in a 'look at my popular github repo with oh so many stars, aren't I popular, oh btw hire me pls' world now, that is actually a big deal.
The question is not, 'should I use GPL?', because the answer is no, if you want to have a successful popular open source project.
The question is; how do we actually change the perception of GPL so the answer becomes yes?
I'm not sure... but I think it's a far more important question.
(I can certainly say that I no longer use the GPL, after using it for many years, largely because it was requested I remove it from projects. What do you do in that situation? Since I really don't care that much why not just put it under something else? I don't have a good answer.)