Guys I have registered on this forum just to solve your wifi issue. I have C7 OLED for a year now and had those issues from day one, I could never use Netflix or YouTube on my TV which is just about 5 meters from the router.
BUT I all I had to do is to change router settings and the same applies to Samsung Toshiba and other TV's.
Make sure your set your 5G and 2G wireless more to the following and it will be all fine. You can never leave it on mixed signal, that'a very important. Since then I'm always connecting to my 5G and get up to 100Mbps.