Originally Posted by
u235
Pedals are susceptible to galvanic corrosion. Steel spindles and aluminum arms. No doubt people overtightning is a cause but not the only one.
This
I've got the same tube of white grease from decades ago that I use for seat posts and pedal threads.
Always grease threads, and even after years only a tap of a mallet or hammer will release a pedal, even if tightened reasonably.