Do I think they're going to fold under? Nah. They're a bunch of spergs and furry degenerates, but they're competent voice actors and they have studios on hand that they can work out of. I think they'll stay afloat doing VA work, so long as they don't sabotage business relationships with hyped up completion dates and timeframes like they did their fanbase. I wouldn't be surprised if they shutter their YouTube brand after another year and another scripted tearfest.
As much as I want to agree with you about the voice actor part, as long as Toei's breathing down both TFS and Funi's necks, Kaiser, Lani and Taka are never going to get constant credits under their belts unless they move to LA or Funi drops their contracts with Toei, neither of which are going to happen any time soon as all three (and their other actors) are based out of Texas by default and Funi exists
because of Toei. And keep in mind, outside of Xenoverse (which afaik, Toei had little involvement with beyond cutscenes) and cameos in Resurrection F, One Piece Film Gold and that unaired version of DBZ Kai's reenactment scene, nearly all of their professional credits have been for non-Toei produced efforts like Ping Pong, Heavy Object and RWBY, often in just an additional voice/walla group capacity. Hells is probably one of the only dubs to have them in act in any major roles, and that's mainly because they produced it themselves.
As for TFS as a whole... Hate to say it, but they were never all that funny even in their early days. For every joke that landed and recharacterization that worked, there was always two more of each that failed miserably and ended up worse than their official counterparts. Their LPs solely hinge on the gimmick of being voiced in character as the DBZA versions of the characters and every other abridged effort they tried either sucks or died after a few episodes. By the time of the Cell Saga, I was wondering if they were simply not reanimating it because it was easier to just edit the footage. Because the amount of Kai-tier animation tweaks and additions they kept doing by the end stick out like a sore thumb on the 90s animation footage. Plus the amount of "emotional" moments got to the point where the impact ended up flatlining very early on.
I'm not at all surprised they got burned out and the combined autism between them, their fans and detractors, and Toei's legal team got tiresome incredibly quickly for everyone else just watching the series. I'm honestly glad they're stopping before the series gets any worse than it already has. Buu would have been an unmitigated disaster with these guys (and it already proved it couldn't be Kai'd without spending nearly half the length of the first series to do so).