Every mountain bike from the mighty downhill bike to the humble hardtail is getting longer (wheelbase and reach), lower (bottom bracket height) and slacker (head tube angle) with each generation. This is fantastic for a big guy like me.
Ten years ago, I was riding bikes with a 45cm reach (size XL). There were few exceptions that were markedly longer, and they were seen as freaks.
My five year old Trek Slash was a full size larger, with a 48cm reach (again, size XL). Comments were offered that it finally looked like I had a bike that fit me.
But now it seems too small. All three of my newer MTB are another size larger again than the Slash. It is fine if I ride it a few times in a row but as soon as I jump on it from any of the other bikes, it feels too short.
In 2021, I ordered the new model Slash. It is another full size larger again than the one I'm riding today. If the bike industry wasn't currently a disaster of supply and demand, I'd have had my new Slash since December. Instead my delivery date is early February.

So tall guys are finally getting bikes that fit.

But on the shorter end of things, bikes are also growing and I think they're growing away from the shorter riders who were well served with the old-school bikes. An average woman who was well fitted on a size Small with a 40cm reach will now find most bikes that size with a 42 or even a 43cm reach. That's a full size larger - effectively a Medium - and too long for those short of arm and torso.
Really what should have happened is the Small remained suitably small with larger sizes added on top. The problem with that is making 6 or 7 sizes of bikes instead of 4. No profits in that. When something like 5% of a typical bike is sold in size XL, spreading those few sales across multiple sizes is never going to work.