Not being paid doesn't mean less biased.
To the contrary: I expect a high bias since you choose to spend lots of time on it despite not being paid for it
I am still aware of both protocols, I still don't like Matrix and think XMPP is "good enough", or at least the best choice. Having an opinion doesn't make me biased against one or the other.
Not being paid for the work on something doesn't imply no bias towards it.
> Having an opinion doesn't make me biased against one or the other.
It might: Confirmation bias