I'm having a similar problem with a Samsung S21U after a screen replacement but mine is having wifi issues primarily on 5G, it is working but significantly reduced range and speeds.
Repair shop said they can't replace the wifi antenna without replacing the cellular antennas also and that would require calibration the shop wasn't equipped to do. I suspect they lied but they aren't going to fix this so now it's on me.
A network connection settings reset did not help. Are there any other options?