They're trying to slowly move up market. I assume soon the $20 will get its own restrictions in the future (and/or ads) to get people to pay $100.

The same could have been claimed in 2024 when they introduced the $200 Pro plan. Nothing is over yet just because of what could possibly happen next.

Yes, and now they (will) have ads in the lower tiers and eventually will add them in higher tiers as well. It's no different to Netflix's methods. Therefore the statement would have been proven right if it were claimed back then.

But these are, again, additional tiers.

You can't just say because they've added more things the old things are over - the old things actually have to go away first. Eventually they may get there (or not). It may be another few years (or not). Nothing is actually now over though any more than it was now over in 2024.

Additional tiers to get people to move up as they enshittify the lower tiers. We already see it in other companies as well as OpenAI themselves so my inference is based on that, not to wait and see until they do indeed enshittify it.