Should I use 2x4 or 1x4 strapping for bathroom ceiling drywall on attic trusses

I’m redoing a bathroom ceiling and could use some advice.

My attic trusses are spaced 24" apart and not all perfectly even, so I added strapping across them to get a flat surface for drywall. I used 2x4s on flat as strapping (perpendicular to the trusses), and now all the trusses are tied together.

Here are my questions:

Is using 2x4s as strapping a bad idea because they’re too rigid?

Would 1x4 strapping be better since it’s strong enough to hold drywall but has more flexibility to move with the trusses?

Could rigid 2x4 strapping contribute to truss damage or drywall cracking down the line (from truss uplift/seasonal movement)?

For reference, the room is a bathroom, so I’ll be using 5/8" moisture-resistant drywall.

I already have the 2x4 strapping in, but I’m debating whether I should swap it out for 1x4 before closing up the ceiling.

Any framers, drywallers, or DIYers with experience — I’d love your input before I go further.