My iPhone is charging from my MacBook. I believe that it charges too fast and even heats quite sensibly. Also, I'm afraid the battery could degrade at a greater rate with such a fast charge.
So, I don't need that fast charging, because it has plenty of time to charge.
As you can see, the battery temperature rises quite a bit.
By the end of the charge, the temperature drops to 30 degrees.
I'm well aware that there's a new thing that analyses how much time you let the phone be on charge and slows down the charging rate accordingly, but only after the battery reaches 80% (more details here - https://support.apple.com/en-us/HT210512)
What can I do apart from just buying a cheap charger? (I don't think it's a great idea)