There's this concept in capitalism/business called oversaturation. If everyone does the same thing, with the same methods and presentation, eventually no one will want the product that's being offered.
Look at the Netflix model. For a long time, it was helping to combat pirating and torrenting with its accessible (and growing) library, all for a very low and convenient price that piraters were willing to pay for in exchange for the convenience of having their favorite movies and shows right there without needing to go through the whole VPN/torrent process. Since Netflix had its boom in 2011/12ish, other companies like Disney, Warner, Amazon, even NBC, are jumping on the opportunity to copy them. As a result, Netflix is losing a lot of the titles that drew people in in the first place (as they're legally bound to be offered on those alternative streaming services instead).
Now guess what's happening? People are cutting their subscriptions and going back to pirating. They've created the very problem they tried to solve with it. All because every company tried to hop on the bandwagon and oversaturated the market. Nobody is going to spend $60-$80 a month on 8 different subscriptions to watch their shows/movies when they could just download everything for free, so long as they know where to look.
The weird thing with Tapas is that they seem to be doing things the opposite way around. When Tapas was still 'new', back in the early 2010's, they were definitely easy to pick out from the flock for good reasons - their look, their functionality, their library, etc. But now they're falling into that cookie cutter mentality that a newer company would be doing, for the sake of 'playing it safe'. They're too old now to be getting skittish and copying 'what's popular' in an attempt to play it safe. The chance to be skittish was years ago, not now when it's more important than ever to start innovating, when every website is the same and people are itching for something new that doesn't look like a Webtoons clone. Just look at the SmackJeeves community, the lot of them jumped ship the moment NHN took over, and for good reason: if they wanted to use a Webtoons clone, they would stick to using Webtoons.
The point against your own argument is in your post: "Lezhin has good sales. Webtoons has adopted coins. There are lots of platforms like this."
So why use Tapas when websites like Lezhin and Webtoons are right next door and doing it better? This is why it's dangerous to play it safe. You run the risk of becoming irrelevant.
It's true! You don't see whatever complaints the LINE Webtoon users have because they just have no way of being heard. In fact, a lot of LINE Webtoon related discussion ends up here.
I've seen it a ton of times, that people don't "care" what the forum users think, etc. But honestly, it's just because the forum isn't advertised or accessible on the app. Everything we're seeing now isn't just "a few butthurt people", it's a preview of what would happen if the forums were more accessible and integrated into the main site than they are now. I've picked my bones with staff already that they should consider themselves lucky the forums aren't more accessible lol It seems to stress them out enough as it is dealing with a thread with 30+ people updating at once, could you imagine thousands? Yikes.
I really like GlobalComix. It's still not my primary platform as I've still got my LINE Webtoons community and GC has yet to catch up with my extremely large buffer of already finished chapters (it'll take like a year of weekly updates for it to catch up, and then some lol) And honestly, a lot of the things I like about it aren't even really seen on the surface level - it's within the community. The GC staff is very small but they're very open to discussion and questions/concerns/etc. on an actual level that's communicative and not passive aggressive or complacent. That line of communication could very well tighten as they grow, but I've got a lot of faith that they won't ever lose it entirely because they value communication right up there with their mission statement.
The biggest "flaw" it has is just the fact that you're not going to be gaining a reader list of 1k+ any time soon. Like, the first person who ever hits 1k over there will be setting a milestone for the platform as well xD But that's not so much a "flaw" as it is an expectation for a website that's still brand new and growing. I think lately they've been hitting a curve in their readership and creator base (right now they're focusing on pulling creators over so they'll actually have content to provide to readers) which is really great to see. I'm hoping we'll start seeing a bigger reader community in the coming year or so, but the big hurdle right now is pulling in creators first and foremost. Can't very well have readers if there's nothing to read 
We're all doing our part to help it out as well because even if it's not "better than Tapas", having alternatives is a good thing. It gives people options. A lot of people's doubts with wanting to try other platforms is just because they don't really have a lot of options, and they've been led to believe it's either LINE, Tapas, or bust. Especially now that every website seems to be copying LINE, it's like, hey, take your pick, LINE Webtoons, LINE Webtoons clone #1, or LINE Webtoons clone #2. Or this old outdated php/BBcode website from 2002 that hasn't updated its look ever since lol GC is, at the very least, presenting options that are new and not the same schtick as what everyone else is doing. And judging from the staff's perspective on it, I don't think we'll have to worry about such a thing happening any time soon.
