Wow. I’d like to thank you for all of the info, it is difficult to obtain information from older devices. People don’t discuss them much anymore, and if I were to post a thread, responses are almost always extremely minimal. You’ve given me a lot of cool info, thank you.
That said, I am surprised. Safari freezing? I thought that was a 32-bit thing by now. I didn’t even know the Air 2 suffered from that on iPadOS 15 as well. I have access to two A9X and A10 iPads (The iPad 6th Gen is a family member’s, not mine. You know I have the 9.7-inch iPad Pro), and they both work really well on iOS 12. I didn’t notice tab reloads… until I got the iPad Air 5. I have it on iPadOS 15 and this device is so utterly perfect! That said, I can’t recall how it performed on iOS 9 in that regard. I’ve stated before that it isn’t something I pay attention to, so I don’t really remember. I can say, however, that Safari performance is good. It has never frozen on me or had any issues, barring reloads.
Two very important and noticeable issues: keyboard lag (I don’t update anything, ever, so I am NOT used to that. I emphasize the not because I’ve never had to deal with that in my 12-year history of using iOS devices). It bothers me. A lot. It is not abhorrent, but very noticeable to me, because I expect it not to be there. I can type as fast as possible on my Air 5 and it never lags. I expect top-notch performance and battery life. I would’ve been fine with the 9.7-inch iPad Pro if it were perfect (which it was… on iOS 9), but I wanted to upgrade as soon as I was forced out of it. Apart from that, it is quite perfect. I’ve tried some games and they work flawlessly, there is no difference there compared to iOS 9. Which is huge for me. I truly expected it to be unusable, perhaps used to seeing 32-bit devices’ destruction from iOS updates. I thought “I am being forced to updated it through three major updates? Three?! Say goodbye to the iPad”. I can happily say that it wasn’t the case.
And the other issue is battery life, like I’ve stated. A 30-40% drop, immediate and irrecoverable. It isn’t absolutely abhorrent (around 10 hours), but it is very poor for my expectations.
Like you said, I might be underestimating the impact of 2GB of RAM on iPadOS 15. Luckily both of the iPads I have access to with that spec are on iOS 12. It is a shame that Apple gave the 9.7-inch iPad Pro 2GB of RAM, the best iPad with the original design language could’ve been even better if it hadn’t been shorthanded by being the only iPad Pro to have less than 4GB.
And a final message to OP: Hopefully this conversation has showed you that performance expectations vary person to person. The best option would be for you to try it.