This is not a good thing at all. This will destroy all really long term cold storage setups, cause a lot of congestion and security risk. The rest of the proposal is fine with me.
I am of the same opinion. It would be a disaster to all of us who have cold wallets. After all, in my opinion the legacy UTXOs should not be blocked but instead the responsibility should fall on our own shoulders. Much like it is when you choose a password, it is your responsibility to pick one that is secure.
This kind of blockage reminds me of all the other shitcoins that 'progress' from V1 to V2, leaving behind everybody who purchased the shitcoin and decided to not check out the charts or the Cryptocurrency news for an year. You get wrecked and you have no idea.
It could also be a disaster if a relative passes away and although it is known who the heirs are, they did not find a way to enter the cold storage and finally get their hands onto the keys in time.
What about collectibles with Bitcoin on them? All of them will have to be either peeled away or kept intact but unusable. Bad idea!