Jeff Geerling did a whole video about you can just use a professional display. It has the option to install a raspberry pi because it's meant to be a display for a store window. This would be a good alternative but $$$.
https://www.sharpnecdisplays.us/products/displays/m551
Note: the reason TVs are cheap now is because they collect data about you. Your data is subsidizing the cost. So if that's the case how much money do they make off you that getting a non smart display costs 4k?
Are there alternative firmwares available for shield?