Counter-point: assuming OP is employed at-will, his employer is free to fire him if they judge his output to be insufficient. But they don’t so... maybe they are fine with the current situation.
Firing people is hard. It can affect morale and send all kind of messages that the founder may not want to send. I'm guessing this will happen at some point, but as a founder who has been faced with this exact kind of situation, I can tell you that it's awful. People who slack can still be liked.
or maybe they are super pressed and would need it to be done faster, but trust the OP that this is simply not possible (because he must work on his side gig)