This seems like a slightly shortsighted reply. KZ has pretty much always been about quantity, having tons of models on the shelves. Often lots of redundancy across a few signature types, usually set within unique shells or variants. Right now they still have well over 10 models readily available for purchase, most of which were released within the last year or two. All the new models coming up are right in line with what they've done in the past, just now with hybrid tech that they've been testing and tweaking with the ZST, ES3, ZS5/6 and ZSR. The biggest difference I see is they've actually announced a plan, unlike before where they would seemingly at random release new models with maybe some leaked info getting out before the model dropped. If anything, announcing all those new models simultaneously could be great for generating early interest.
Considering most of them are 1+1 hybrids, prices are probably going to still be quite low which will continue to attend to their bread-and-butter market. And, going more upscale with other models has been EXACTLY what people have been asking for for years. Just peruse this thread. First it was hybrids. We've got that now. Then it was something pricier and more upscale, but still affordable. The ZS6 was a good go at it. The ZS10 might be just the thing though given its a 5 driver hybrid with a crossover. I'm personally looking forward to seeing what they do with this new lineup and will be reserving judgment till I try them out for myself. They could be a horrendous abomination, sure, but they could also be amazing.
Their plastics have also been quite good over the years, with the exception of some of their really old models like the DS. Their current plastic bodied iems still feel better than a lot of more expensive products, like those from Sennheiser, JVC, Marley, Sony, and other name brands, not to mention comparing to similarly priced Chi-Fi offerings like the BGVP DN1 which feels as cheap as it is. The ZS6 is crazy overbuilt for the price though, and I definitely wouldn't complain if they applied that quality to the full lineup. That said, as long as their plastics remain at least as dense and durable as what they're using for their current lineup, they'll be just fine.
Lastly, having heard lots of totl and reference gear, I'm even more pleased with my KZ collection. Would rather have multiple good earphones of varying signatures than one amazing earphone with one signature.