Just play what you like. What's more important is how well you can perform on any particular class you've chosen and how well you understand the fight. PF groups that lock for meta comps give me the impression of someone lacking confidence, someone who is looking to be carried by a meta advantage. It's one thing to prefer a comp, but another to require it, full stop. I don't understand the mentally behind wanting harder content, yet demanding the absolute "best" possible comp in an attempt to make things easier.

People will beg for a challenge then bend over backwards to try and preemptively make the fight less of a challenge. On one end of the spectrum you have groups that intentionally run with unusual comps just to experiment and prove that it can be done.
On the other end, you have people who won't run unless they have the perceived meta advantage.

Lastly, do people realize that the meta is being set by world firsters and people competing for the fastest possible progression times in a competition? These are highly coordinated groups.
These groups set the meta, but they aren't exactly playing the same game that a pug is playing. Your average PF pug is just a bunch of random uncoordinated people thrown together.
Aren't meta comps built up around coordination and team synergy? If so, isn't the average uncoordinated pug going to get less mileage out of a meta comp anyway?