I looked in to this about a year ago and found that many digital sign models either (a) omitted relatively basic features like HDR, HDMI ARC, or CEC or (b) weren’t 10% or even 50% higher priced, but 200-300% more (compared to fairly high-end consumer models, not to the cheapest consumer model).
Make sure they actually do what you want, even things that every consumer model has had for years. The situation may have improved in the last year. Also, I only looked at 82-85” models, so the situation may be better on smaller models.
