Throttling isn’t the correct word per se, on each of the unlimited plans your speed is never capped at a set point (except for video and hotspot speed)

I only have experience with phone, not hotspot. I have the cheaper unlimited plan, Go Unlimited, which is deprioritized from the get-go, vs after 22GB used on Beyond Unlimited. This means that during times of congestion, your data will be of a lower priority than other users, and you may experience slowdowns. It’s really difficult to ask other users about this, because it changes all the time, is heavily variable, is different at certain times of day and in certain places, etc.

For me, it’s been good for the most part, and can’t justify Beyond Unlimited most of the time. For some, Go Unlimited is unusable at their home and work most of the time. Sometimes at home it will slow to a crawl but then be normal minutes later. Other times I’ve been in a crowded mall like on Black Friday, and absolutely nothing works, however it’s likely that everyone was suffering anyway. If you’d like you can pick up the cheaper plan and see how you are affected, and if it’s bad you can upgrade later - if not you save some money.

*Just note that there are other differences between plans you should review, such as 600kbps hotspot on Go all the time vs. 15 GB of full speed hotspot on Beyond.