One pinhole is bad luck. Two or three in a year is a pattern, and it means the pipe wall has thinned throughout the system, not just where it happened to fail. Patching each one is money spent waiting for the next.
This combination is the signature of galvanized steel corroding from the inside. The rust narrows the pipe, so pressure drops, and flakes come out at the tap. There is no repair for it, only replacement.
Grey plastic pipe with crimped fittings, installed roughly between the late 1970s and mid 1990s, is polybutylene. It becomes brittle and fails at the fittings, often without warning. Insurers frequently ask about it. If you have it, plan a replacement rather than waiting.
If flushing a toilet noticeably weakens the shower, the effective diameter of your supply lines has narrowed. In an original galvanized system this is corrosion. It rarely improves.
Add together what you have spent on plumbing repairs in the past two years. If it is approaching a third of a repipe quote and the leaks are recurring rather than accidental, the arithmetic has already made the decision.
If walls are opening for a kitchen or bathroom remodel, repiping at the same time costs dramatically less than doing it later, because the expensive part is access and drywall repair, not pipe.
Buyers' inspections find old galvanized and polybutylene. It becomes a negotiation point that costs more than doing the work on your own terms and timeline.
A real plumber, a flat-rate quote, any hour of the day.