Q: Only the drivers back tire rubs on the wheel well when going over bumps and sharp turns

My car has been lowered with lowered springs and I was told by a mechanic that the reason from the rubbing was "probably" because the driver's side front strut is leaking oil. He then suggested that I have the strut replaced but also it's not a guaranteed fix.

When he was showing me this I noticed there was probably a miscommunication between him and the receptionist because I said the rubbing was happening in the back of the driver's side and not the front. You can actually see a lot wear on the face of the back tire. He didn't realize this but continued to suggest it's still probably the front strut that needs to be replaced. He said once the front one was replaced that the back tire wouldn't probably rub anymore.

This problem started when I changed that tire to the original size. I had 2 wheel alignments with a smaller spare tire and I was thinking those wheel alignment on a smaller tire has caused the rubbing thats happening now. Is this possible.

My car has 188000 miles.
My car has a manual transmission.