Let's starts with the basics...
The light will come on for a few reasons...
1) Low oil levels...may not have been filled up properly / completely or you could have oil leaks or oil consumption....engine burning oil slowly...
2) Viscosity of the oil oil weak...if cheap oil was used, it can break down prematurely...
3) Partially clogged oil filter (may not have been changed or changed with wrong one
during the last oil change).
4 Weak oil pump...due to age...not really likely!
Here are a few views......Now...Just a point of thought, I change my oil and filter e dry 15,000
miles...periods! I use synthetic oil by Castrol GTX SAE30....not 10W or oil with HD in it...just SAE30...
I have vehicles with 185,000 miles and up...All working perfectly...
I hope this was able to help you....Good Luck....