some yapping from me. my 2 cents regarding 8gen2 vs 8gen3. my experience is quite different, especially in regards to heavy gaming (i play both genshin and honkai star rail on mobile). maybe it just so happens that the one 8gen3 phone I've tested is tuned well, but my experience with it is noticeably better than any 8gen2 phone i've used. my theory is actually that it depends a lot on the "tuning" approach that each brand takes, because just chip alone, all the in-depth testing I've seen show that 8gen3 has higher performance per watt compared to the 8gen2 (see image below). no matter peak performance, mid level performance, or at the lower end of things. for eg, the CPU portion. to get 5000 points in Geekbench 6, 8gen2 needed 6W while 8gen3 only needed 4W.
i think the main thing is just that these newer generation of chips has the ability to draw a lot more power in order to get much higher performance, basically, higher ceiling. this is likely to improve its "burst" performance like initial app launch, things that require fast processing like video/photo processing, etc. kinda like intel turbo boost i think? give it more power when it needs to brute force and do what it needs to do quickly, then quickly drop power once it's done.
but then some brands might not be managing all that well and instead letting apps make use of higher power for longer than needed, which gives the impression that it is more hot? like you see these chips can go over 10W in term of CPU or GPU usage which looks nuts... but even running Genshin at highest graphics option normally uses like 5-6W in total only.
anyway, in my own experience at least, redmagic typically just F it and don't limit the processor too much. I've used 5S, 6, 7 Pro, 7S Pro, and all behaved like that. the 7 Pro with 8 Gen 1 in particular was something special. lol. pretty sure body temp can easily reach over 50 deg even with fan turned on. lol.
OnePlus tends to be more willing to let the phone runs warmer as well to ensure that games run smoother, especially in gaming mode. like the OP11 and Ace 3 with 8Gen2, both ran noticeably hotter compared to my Redmi K70 Pro with 8Gen3, and Xiaomi tends to be more conservative in my experience with the 13, the Poco F5 Pro, F5, when talking about more recent devices. by the way, when playing the genshin at the highest graphics settings, the K70 Pro drained about the same level of battery over 30mins as the Ace 3, and that is despite a much smaller battery, and running the game at 864P render resolution instead of 720P like on the Ace 3. and the phone didn't get nearly as hot as the Ace 3. which is why i do think 8Gen3 is a better chip.
as a side note, samsung usually is the worse when it comes to gaming since they are not only using stacked motherboard, but also a lot less heat dissipating/spreading stuff in their phones. S23 Ultra with 8Gen2 is the worse performing phone I've tested with 8Gen2 (the OP11 is so much better that it's not even funny, and it even loses to foldable like the oppo find n3) and even performed no better then phones I've tested with 8+Gen1. but this is just talking about my gaming experience with these devices of course. ¯\_(ツ)_/¯