It is certainly not usable for the average person in it's current state, hence why I suggest donating to it to help with developing it. With proper funding and full-time devs, it would be able to focus on adding proper support to more phones, or potentially partner with a manufacturer like GrapheneOS just did with Motorola to get first-class support on a smaller handful of devices. Postmarket is our only long-term mobile option that will remain FLOSS and in the users best interest, we just have to support it and help build it up into something we can all use :)