Exactly same what I'm facing with A50 after this latest update .
sometimes the phone is draining battery too fast even facing problem with earphones
I would guess that it's a bit of both. as updates keep rolling out, it's adding stuff on top of what already exist.
The only way to lessen the load is to keep the device less bloated from data, so... clearing up RAM space, uninstalling unused apps to free up storages and such, like how you would with PC's.
Either way, do keep in mind that A series are lower end products with comparably weaker processing power parts, so it will tend to last shorter time than flagship phones.
If it's slower by a significant amount, then it might be an issue, but i'm talking about like... you have to wait a minute for things to load and such.