Because it is

If it has anything but the team branding, the sponsors should subsidize the price of the shirt.

He’s completely right. It is an insane rip off! I’m not a f1 merch buyer, simply because I think if I’m going to be a walking corporate sponsor, I should be payed for it, not paying!
Everybody should just quit buying that trash. Or don’t and just get ripped off. Your choice.

It’s a complete ripoff.

This is every major sport out there. Almost any jersey from any sport under 100 US dollars are built the same way. Luckily a lot of other sports still have full embroidery options, and thicker materials, but they also cost A LOT more.