I have no knowledge to share on Pono ukes. I will offer that this is a common thing that I have seen with many instruments over the years. I rarely hear that those being produced now are better than ever. There is always a tale of a golden age, instruments of certain serial numbers, etc. It always seems to be that the good stuff is stuff you can't get anymore.
The new Pono Masters Series has been touted as being better than the previous Ponos. Lattice bracing vs. fan bracing.
The newest revision of Ko'Aloha tenors with a shorter neck, moved bridge and revised unibrace and its positioning has received excellent reviews for a more balanced sound than the previous KTM-00 iteration. (I've owned 3 KTM tenor versions from the 2004 Crown Bridge to my present 2017. Each was an improvement from the earlier version.)
The Kanile'a K-1T tenor has improved with the each revision of the bracing system. They are small improvements, but improvements nonetheless.
I can only speak to tenor ukuleles that I have tried or owned and in general, I think the overall quality of the available instruments have improved markedly. People have had to up their game to compete.
Sure, there are lots of examples of diminished quality in some models by some brands. I think Martin is perhaps an example of that. Their current builds don't seem to be as good as their vintage models. But then again many reviewers have stated that the Konter Soprano sounds and feels very much like a vintage Martin soprano. (I absolutely
detest the cheap, roughly made, loose-grained bridges Martin puts on their tenors.)
I do agree that the wood quality used in many builds has gone down due to availability and cost. For instance, how many one-pice tops and backs are made? Tight grained spruce is getting harder to find. Curly and flamed koa is becoming scarce. Yet, some brands have started putting solid wood tops on previous all-laminate models. And offering solid wood versions of their laminate instruments.
So I think some things are "cheaply" made compared to a few years ago. While others have been improved and are of a more consistent quality. Better/worse? A little of both I'd say.