I used the API version for quite a while before using a subscription, which I now have used extensively for many months.

So, is your claim that they just slow down and queue the subscription version, or are you accusing them of using nerfed models, or is it something else? The only time I ever get some slowness has to do with the models being overloaded and has nothing to do with limits. Those are two separate concepts you seem to be confusing. And luckily, this is pretty rare for me since I don't work during US time zones.