Premiums on coins have been declining for some time as BTC rises. They will never catch up, ever.

In $ terms however premiums on coins has kind of stagnated but then this is no surprise as they are all still relatively "young" and a copper/silver round only has so much value before the ceiling is reached...

Coins, as with much of the Bitcoin Art, things need time to mature and in some cases will need quite some time for them to realise any worthwhile gain. I would say in some cases there needs to be decades pass before values climb again.

Only the ardent collectors are the ones prepared to pay anything worthwhile and even then they are all seeking bargains especially in a bull market.

Expectations are frequently crushed by the reality of market forces despite ever more collectors coming into the space.