low oil pressure, could it be oil pressure switch 2000 chevy sub

There is a pressure regulator built in to oil pump... If it flucuates something is wrong. Could be worn out oil (no viscosity left) or plugged oil filter simple fix. Ive had same problem on every chevy ever owned an seems to lean more towards to much pressure causing oil to overheat an foam then pressure drops alot. You want a high volume of oil moving to cool an lubricate. High pressure means less volume is being moved. Most the time its been crudd in oil pump pressure regulator was the cause. Taking it further i discover cause to he tiny water leaks at intake gaskets alowwing moisture into oil an breaking it down to crud. V8s its the rear intake ports. 4.3v6 its the water tube between upper an lower intakes.