Nothing that is happening changes that contract. If they go against their perpetual license promise, your existing one will still be valid "perpetually."
That's the whole trade: monthly or annual subscriptions give you the flexibility to react to changes to the product. One time payments don't get changes so no need to react.
Saying that designers could have just continued using Photoshop CS on a 2006 MacBook doesn't reflect the reality of hardware updates and the changes in the industry-wide design trends.
The cost of not just learning but becoming a professional user of a specific set of tools is very high. Then later as time goes by being forced to either abandon these tools or to accept a different pricing model is - to many people - unfair and unethical.
Looking at Adobe multiple versions have phased out online activation support over the years, with a not uncommon complaint being trouble installing and using purchases subsequently. As with anything tied to server checks one has to trust it will either continue working or workarounds be provided.
IIRC Clip Studio Paint switched their activation method in the last few years as well.
$100 or so for the full suite. Great for the few times a year you need to use a tool. Even though I'm more on the tech side, I spent enough time in photoshop/etc around web development at one point that it's handy to have.
This would cost more in a month or two on a subscription.
I don't anticipate the current version licensing being revoked.
Future versions might add a subscription, but my feeling is if the TAM for them is all of Adobe's subscription clients, there's probably a lot more customers they can absorb.