Actually not anymore. There’s been a recent breakthrough that led to a new exploit up to 11.00 being possible now. 11.00 is from, like, late 2022 I think? Obviously not an option if your PS4 has been in regular use recently, but I lucked out and got an 11.00 console from a friend of mine who hadn’t been using the PS4 for a while.

If you’re on a newer firmware, there is no way of reverting back to 11.00, unfortunately, unless you’re up for some soldering.