While many promotional and marketing images might lead you to believe that a 75-inch TV is too big for a living room, this really isn't the case for lounges of an average size.
So long as you have a table or stand that's accommodating to the TV's large size, and create adequate space for peripherals like soundbars and speakers, a 75-inch TV won't take up as much real estate as you might think. And if you're thinking of mounting a 75-inch TV on wall using one of the best TV wall mounts, you'll also want to consider how much space it'll take up on the wall.
Do keep in mind that you may have to rearrange the room around the TV for the best possible viewing experience, however.