Article with pics in a gun mag some years ago about a WWII bring back mag fully
loaded, dropped in drawer and not touched for something like 50 years. All bullet fed and fired! If today's springs don't hold up, they must be crappy steel.
I have Glock mags that I've had since 1994 and haven't had an issue with, Ive had some others that didn't fare so well. I don't worry about it if they become problematic replace the spring, they are cheap and readily available.