oil pressure light on at idle on 1996 Cadillac DeVille

Oil light flickers when I stop at light and rpms go below 725. Oil level is full, but I also smell hot oil when it happens. I don't smell the oil any other time. Just had an oil flush and pressure tested before this happened. Everything ok.

Just found answer here: Question: Why would oil pressure light come on when car is idling in park or in drive??

Answere from valleyautotech:

You need to have a shop check the oil level and pressure as a mechanical oil pump has low pressure at idle then as the motor revs if gains pressure. If the screen on the oil pump is beginning to clog or the oil pump itself is beginning to fail it can do major internal engine damage if its not addressed,

Asked by for the 1996 Cadillac DeVille
I wonder if flushing the oil system dislodged debris which now be stuck under the oil pressure relieve valve. Why did you flush the system to begin with?
Perhaps it would be worth just changing the oil pressure switch and oil filter and see if the problem goes away if not it would be important to recheck the oil pressure using a mechanical oil pressure gauge.
If left un-attended major damage could/will occur.
Took to Firestone for brake problem and they said I needed complete brake overhaul which would cost close to $800 for that alone, but also had oil and coolant leaking into the engine, possible bad head gasket. got a second opinion from a more trustworthy source had brakes repaired and did the flush to test for the other problem (found nothing wrong), total cost under $400. But now this light problem. engine runs perfect. no overheating, runs at 206 degrees when hot.

If debris was causing the problem, woudn't it there also be a problem at driving speeds? What kind of damage would happen, would it be accumulative or sudden? Just wondering if something would happen on the way to the mechanic, what to look for.