After all the whiny reviews regarding it in particular on YouTube, the first disc I popped in was "The Android Invasion" so I could whine with the rest'n'best of them...
Yeah, there are telltale signs and I don't think the 16mm prints survive as there's no way that the exterior footage would be so clean yet with oversharpened elements, the type of "grain" in the background, and other telltale signs. Add in "phasing" fabric wrinkles, scratches and other marks that disappear and/or reappear, etc, and it's clearly had upscaling settings set way too high. Indeed, the closest allusion is the end result being as much a giveaway as what painting a big circular target bright pink with neon yellow center will do for archers trying to make their bullseye that much easier. Unlike the androids in this story who keep missing so often on cue (which is a sign of bad scripting unless it's that one scene from Blake's 7 where Avon points out that the guards were SUPPOSED to miss because of a bigger plan in mind, but I digress).
Is it all that terrible? Honestly, not really, it isn't. But it's not good, the previous season sets still do look more consistently better, and it is fairly obvious to anyone even remotely knowledgeable. Especially when previous season sets didn't look so obvious with the technologies used. Or are we supposed to say "tech" now... plus, the DW stories in their mix of videotape and telecined 16mm film elements are largely all that exists. (pay attention to when the real film elements were found and reinserted and the difference is night vs day. All of season 19's stories have their 16mm prints surviving, miraculously.)
The set is still worth getting and new technologies are invariably going to be tried out, with this season set being an early release making use of it. Either a couple of enhancement settings were set too high, they ran out of time to refine a re-processing, or they're using a different upscale package.
That said, previous seasons also had a lot more manual work to complement the AI routines. And it shows. And was too often the better for it.
On edit: I nailed it, where's my Kewpie doll, as "The Android Invasion"'s 16mm films do not exist and the blu-ray release:
https://chuckipedia.ca/index.php?title=Surviving_16mm_Film_Inserts_in_''Doctor_Who''
Also, why does "Kewpie" remind me of "cowpie"? Oh well...