Yeah I can't speak on the recent quality, I haven't seen much TNA these last couple years, I trust that it's totally fine and no doubt quite enjoyable to a lot of people. To which I say: good.
But their attendance numbers and all other metrics don't really mean anything to me. They're getting these numbers because they've become, in essence, the sister brand to NXT. Things were trending positively before Scott got canned and the WWE partnership started, but the crossovers with WWE have clearly accelerated their improvement from a business perspective. That's all well and good, but there's absolutely no universe where WWE eventually says "alright, it's been cool collaborating with y'all, we're going to just let you guys go on your own path now that things are looking good". They're clearly going to keep them under their thumb for as long as it's beneficial, probably will try to purchase them I imagine, and if they do eventually separate, then the numbers for TNA will quickly fall off and they'll be left back at square one having lost their identity and a lot of their longtime fans. None of that is to say that people shouldn't enjoy TNA now, and that the company themselves shouldn't be happy with the good business they're doing, but it's very easy to see that this doesn't just end with TNA flourishing independently.
Once again, I know there are a lot of positives for a lot of people that are coming from their work with WWE, and I don't even blame WWE for doing what they're doing, but as someone who has been a TNA mark for 20 years, I certainly lament that the company wasn't really even given a chance to rebuild independently, and that the spirit of TNA that Scott D'Amore specifically represented and wanted to revitalize is probably never coming back.