In the room shown it would def be possible to mount a tv lower enough to enjoy. Use a swivel mount to ensure. I have a much used fireplace in the lounge and the surrounds and mantel don’t get hot at all.

A big cause of premature electronic failure is excessive heat so I'd be wary of putting an expensive $3000 TV above a "real" gas, coal or log fire that emits a lot of rising heat.

The fires you see mounted below TV's in glossy magazines are usually ethanol burners which I think don't produce as much heat so would be a safer option.

To stop the heat traveling directly into the TV ventilation slots, it should be mounted in a recess like this.

ethanol fire

The angle of your couch may be an issue too. But if it is a real fire, mounting height will be fairly high which is not desirable unless sitting in a recliner.

I'm not sure if that is your house , or just an example ?

In that picture , I'd get a bigger TV ( because why not ) and mount it further along the wall , and spin the L shaped couch around so that it sits in that corner , the fire is near , the TV can still be seen from the couch .

And depending what the climate is like where you are , and if you have other heating , such as heat pumps etc , you might only use the fire 3 or 4 months a year , plus the occassional night when you have visitors and want to project a warmth haha -- rest of the time make your family go cold , or use a $20 fan heater haha .

We have had our TV mounted above our fireplace in our last house and will do in our current build.

There is regulations about the distance based on the fireplace, and your fireplace manufacturer will tell you what the safe distance is, ours is a zero clearance fireplace which means they can pretty much touch and be safe.