I think the "my book" shirt is pretty funny. Good use of the classic color scheme. I wouldn't buy one, though.
I don't have an issue with his desire to create a merch shop. I would ask why it took so long, but I think he realizes that it's not a great idea. exJWs --particularly the newly-out who are likely drawn to his channel-- will not be inclined to advertize their situation with merchandise. Especially t-shirts. They will probably recognize it as a tasteless or tone-deaf move. So this isn't for them.
This is for the remaining saps who still send him money and haven't given up yet. It's a way to take even more of their money while he continues to struggle to produce content. In order to draw more interest and sales, he'll need to branch out. But what can he add that isn't JW-related? Merchandise attacking religion? Promoting atheism? Pushing his vendetta? What? What can he produce that people would want to buy?
I can't think of anything. And a merch shop will not resolve the issue of the slow content rollout and the lack of enthusiam and lack of direction he has been showing for months, now. It just means that when the grift finally ends, the amount of money he will have drained from people's wallets will be that much larger. I can't say it enough: this is the man you are supporting with your dollars. At this point, you deserve to get ripped off.