My guess is that the conceptual winnowing will continue. As today, 95-99% early H-Es, especially N-frames, pre-model and later P&R 98-99% - S&W .44 Magnums in cases, ditto N-frame .357s [particularly in orig factory cases with accessories], Colt Pythons, Colt SAAs of early to mid vintage, original US 1911s, English cased double rifles and shotguns in excellent condition.
Look at the guns some of our noted contributors display here, including provenance materials. They can pick them now, and they are right on track for the future, in my opinion.
The kinds of arms that I select as a small accumulator are of blended utility and attraction. Neither their condition [usually], nor their rarity will commend them to the future at a rate higher than inflation, in my opinion. That's OK - and it beats a lot of stocks my advisers have chosen in the last 11 years!
Regards,
Dyson