I think the biggest issue is gameplay; most people don't start over from scratch after a big update or... they do so in a server environment where there's usually always a bit of an economy in place which allows you to gain certain items in a completely different way.
But if you look solely at gameplay and what was added there then... yeah, it's not all that much. A lot of the additions are cosmetic and most of the newer features are end game. Allays sound like fun but are actually pretty useless. A death compass sounds fun, but considering that you need to get to the "most dangerous place in Minecraft" you might as well skip that part entirely.
IMO Mojang don't pay enough attention to gameplay. I recently started a new game and it was fun enough but... why do I end up with a massive excess in copper and hardly any iron? It's annoying, frustrating even if you consider that copper is far less common than iron in the real world, and didn't they want to mimic the real world as best as possible? But most of all copper is still pretty much useless other than a cosmetic building block, and that just gets annoying IMO.
Surely you could have seen this coming? But naah. Even if they would give us something new, maybe something allowing us to combine iron and copper so that we could use that for at least something...
Sure... finding a huge underground cave looks awesome, no argument there. It's much more impressive than the ravines of old. Just too bad that they don't always get you much resources. Not to mention that digging in that stuff is even more time and thus labor intensive, and without giving us anything extra in return.
I kinda gave up on vanilla play because I find it frustrating most of the time, these days I'd rather spend my time on modded Minecraft. Copper is still somewhat useless, but ... at least I can make bronze and brass which do have their uses again (Tinkers FTW).
