I don't know if it possible to define if this is less or more risky, as bitcoiner perspective...
The best solutions are DYI using serious protocols like
https://glacierprotocol.org/ and using open source software like bitcoin core.
There are too many differents makers and exchanges that we cannot generalize as first of all.
Bitcoin has been intended to be digital. Has been intended to be used without a third party.
Of course as decentralized technology anyone could "create" what he prefers or use a hardware wallet ...
You can decide to trust a key maker or some one that "hold" your funds or your keys... but this is not anymore trusting bitcoin and even the fact that you can create a safe wallet completely off line

Its a myth that you need to be a tech expert to secure your bitcoin. Absolutely not, maybe in the early time (<2012 ) for non speaking English it was really hard to buy or to find the proper info about bitcoin.
In both cases, you must not use Exchanges or Collectibles for storing your coins. Why? I see both as what they have to be done, for what they have been inventend for.
Exchanges -> place to buy and sell bitcoin. No storage/custody, unless penny amount for various reasons (lombard? DeFi? Staking?)
Collectibles -> items that can be handled with a small amount of bitcoin. Loaded can be precious but I will never use a wallet made by another one as my "cold wallet" or whatever except the sum "for a collectible".
The argument of custody, could be easily outshined by
https://bitinfocharts.com/bitcoin/wallet/Binance-coldwallet34xp4vRoCGJym3xR7yCVPFHoCNxv4Twseo
wallet: Binance-coldwallet 248,598 BTC ($20,896,743,085)
If they can manage half million btc... I would not argue too much about the security of exchanges...
In any case there are goods/bads/scammers/errors, but it's evident that safety measure adopted in a collectible have a kind of limit despite the same that can be adopted (and changed during the time) in an exchange.

It's evident there is an advantage as resources and people involved. Even as technology since they can access to a new soft fork and enjoy better conditions. Also... no key maker could have an insurance. Exchanges in some countries can offer to cover potential loses.
Here in topic is not mentioned the risk to deal in person - how to sell/buy/logistic of these items.
Selling/exchange crypto collectible in person could be not easy and requires most of the time to involve a third person (escrow) or a third service (that could be a postal service for shipping).
Deal in person bring a risk (I would say an intrinsic risk that bitcoin by itself has in part removed - no middle man - no physical transaction).
There is no a clear regulation, in some cases it can be really hard to retrieve your items if get seized during shipment...
An early adopter few years ago has highlighted to me the advantage of bitcoin as digital medium. This should be the only focus.
If you cannot trust no one, you need to cross a border, you need to save your things, you just need some planned text and nothing more.
With bitcoin you have a rare chance to not rely in third parties. Keymakers or other mediums, like physical items or digital platforms.
Of course anyone should have his idea, but I would see bitcoin as the key stone that can guarantee all of this trust in collectibles or exchanges.