Industry standard M.O. is 10 years max (of course you will see some exceptions, so if a manufacture comment on this and say they support longer than 10 years, my statement is not invalidated). Some companies will hit 5 years and slowly try to fade into the sunset. But by the time it's 5 years, most firmware are stable enough and free from bugs.
BUT, here is the big but. . .if you have any product that has built in streaming capabilities, that capability is built using the streaming services' API to get the stream. These API can change or new API calls for newer features can be added. Or a new streaming services can come onto the market. If your manufacturer stops updating the firmware, well, things will eventually start breaking over time.
But if your speakers take direct digital input, then you can use that.
My systems at home all uses a PC to stream, because I know that streaming service apps will always be up-to-date and any new service will always make an app for the most proliferated OS of all time, Windows (please, this is not a OS discussion, Apple fanboys need not to reply).