There exist things like refresh rate, response time and input lag. If you look into them you will realise why a good monitor is the obvious better choice.
Monitors have better pixel density so even if it's the same resolution, it'll still look better. Also only monitors have features like 1440p, ultrawide, or 144hz refresh rates. It's also imo a pain in the ass to be playing on a 50" tv that's barely 2 feet from your face
Better response rate and refresh rate with monitors. But if your having no issues then stick with it.
My brothers tv gives him alot of issues with games like the resolution being fucked, really bad gamma / brightness and some games even not running because of it (Even though it's a 1920x1080 tv