The kits for one roll are relatively pricy, so I think they are not sold well. Tetenal went through a failed restructuring in 2019 but were saved by a management buyout from Tetenal employees. Curiously the first new products they introduced after that were the MagicBox for C-41 & E-6 film kits (and RA-4 colour paper). I think they are keen to concentrate on popular products.
The Parvovin and Superfix tabs for B&W are a much better product, they can be stored almost indefenetively and are for the same category of low volume users. But I don't know if that is technically possible for color.
Ilford has something similar (also B&W), the Simplicity Starter Pack. All of that to lure beginners into home developing. I would be surprised though if Simplicity is running well, if you compare that to the Tetenal tabs.
I read an article lately [1] where shops are saying they have enormous backlogs in selling rolls, notably to younger users who are accustomed to smartphone photography, and darkrooms are re-erected on schools. So film photography is going well.
[1] Lege schappen en hoge prijzen: het fotorolletje is niet aan te slepen
Please translate from Dutch if you want to read it.