I think that the strap hinge idea is brilliant. To support your thought that the TV is not going to open, I have the bedroom TV on a articulating arm and tight enough at the pivot points that I did not put a catch on it at all.
My cabinets up front are steel, covered with a molded plastic bezel, I really want to cut about 6" off the bottom and build an matching oak bezel. It is simple to do but very messy, cutting the heavy gauge steel would require the use of my 4.5" angle grinder.
The only problem I have run into has been with the angle of viewing in the bedroom. I had to shim the base of the mount so that the TV points down quite a bit. I made some temporary sliding cabinet doors to fill the hole behind the bedroom TV and it has ended up being my wiping rag storage. Too high for the DW to get into.
Great sawdust making.