It doesn’t have to be wireless - in fact that would be preferable due to the latency associated with Bluetooth - the key thing, at least for me, is portability. Something at least as portable as the Prime itself, in terms of size/weight and ability to be battery powered - and without any DSP.
Soundbok looks good, but seems more like serious performance equipment and is very big, heavy and expensive. Plus it has Bluetooth too.
Perhaps no such thing exists, which is understandable as those things are serving a much larger customer base requirement.
Currently, when not just using headphones or hooking up to an amp set up, I’ve got a couple of options, but they are permanently set up in a bedroom (Old Logitech PC speakers) or are used for my TV (Edifier)
Edifier R980T 4" Active Bookshelf Speakers - 2.0 Computer Speaker - Powered Studio Monitor (Pair) https://www.amazon.co.uk/dp/B06XGC7NTX/ref=cm_sw_r_cp_api_fabc_DQv.FbYDG2301