xiaomi – Why does an Android phone with Snapdragon 732G run slower than an Android phone with Snapdragon 678?

I am comparing the two phones:

Xiaomi Poco X3 NFC - Snapdragon 732G (8 nm) - Adreno 618 - Android 10, MIUI 12
Redmi Note 10 - Snapdragon 678 (11 nm) - Adreno 612 - Android 11, MIUI 12

For both of them, if I dual open Pokemon Go using MIUI’s dual app, Redmi Note 10 has smooth graphics on both apps, while Xiaomi Poco X3 NFC is more like 15 frames per second: the graphics is quite lagging.

It was quite strange that I checked the specs of their CPU and GPU, only to find that Poco X3 is supposedly at least 50% faster than Redmi Note 10. The only difference is that Poco X3 is Android 10, while Redmi Note 10 is Android 11.

What is the reason for such drastic difference: a slower CPU and GPU but faster? Is it just due to Android 10 vs 11? It seems Poco X3 won’t update Android officially but I have to rely on some 3rd party installation.