Fair point; to correct for this bias, ask n people to rate their experience with software reliability, then wait five years and do it again. The larger your n, the more you correct for individual variation (via the Law of Large Numbers)

1) asking five years apart only confirms if the bias is stable. It doesn’t correct anything.

2) asking more people gives you an answer closer to the ‘true answer’ (i.e. the mean answer if you asked ‘everyone’). It corrects for sample error, not directional bias.