For those thinking the lack of an on/off button is the problem by design:
I don't think Apple wants a on/off button, nor people would need one if the AirPods max works as they were expected to do.
As apple has stated several times for their products: they want simplicity, they want to work magically!
From their perspective , a on/off button is only adding one more steep to the funnel of the using experience, complicating it. You, depending off a button to save battery.....what if YOU forgot to turn the button off and you loose all the battery. HUMANS forget things, tech doesn't.
Apple wanted to address this issue by eliminating the button and make the headphones smart enough to turn on/off by themselves, making the user experience as simple as just putting on and off the headphone from your head, just as the other AirPods. Magical.
Sadly this product is buggy, but im sure the intention of apple is achieve the best user experience, as simple as possible.