Was John a massive hypocrite? And a sorry excuse for a human, as you said?
I don't think a hypocrite would go to such lengths, pretending to be power-less in a world that treats being regular human as a disability. I do think he wanted to avoid power, both personal and as a king. If anything he wanted to change high tiers to be more friendly. It worked with Sera, but Arlo couldn't settle.
Arlo is no saint either, instead of continuing Rei's work, he just re-created the old system, with him in charge.
Keep in mind this same system decided that since Sera is powerless, she should be abused, since that's the expected normal. Arlo both comes up as extremely prideful and totally ignorant how his system works in practice for anyone else.