In my experience before you see mass layoffs you'll also see some of the following: hiring freezes, benefit cutbacks, travel bans, infrastructure cost cutting, office closures, revamps to employee evaluation processes, etc. Without at least some other factors I wouldn't assume a company is considering layoffs just because they use the word.

If you are laid off in much of the US anyway, you are eligible for unemployment in case that's needed. That might help someone with less assets in a protracted dry spell.

Also very common, you give up severance pay if you quit. If you can afford some timing risk, IMO it's best to have your scope up and be looking just in case, then wait until pushed. The severance will basically be a bonus if you're rehired quickly since you should have some leads lined up.

There have been times in my life when that advice was 100% true, but, not every time.