Yes, RCA is common, even on high end models. Coax aerial connections are also common here in the UK as we have Freeview TV (majority of the UK TV channels are free to receive with any digital aerial and "Freeview" decoder box/TV).

I think RGB SCART is still around here too in a larger way than many realise. my parents got a new TV I set up for them which had an RGB SCART socket. Used it to quickly test out a SNES the other day when visiting and it fucking worked fine lol, looked remarkably good but no match for a proper upscaler obviously