There's two types of ARR raids. The 24-man "Crystal Tower" series is actually very easy and was designed to be clearable by basically anyone, and I think it's well worth checking out as it's generally super neatly designed, although getting in with current queue times might be a thing.

The other high end content comprises Extreme Primals and then The Binding Coil of Bahamut. If you were to take these on with a full party synced to level 50 they could provide anywhere from a bare minimum to a very strenuous challenge... however, you now have Undersized Party as an option. A few level 60 friends could carry you through the majority of the content if they're experienced with it and you want to check it out.

That said, as mentioned? All of these storylines are completely optional, and nothing's really gated behind them except some fancy gear designs and a handful of minions, etc.