Cost is a factor for sample size in any field: but physicists don't publish if they can't accumulate a sufficient sample. As a result physics experiments where sufficient sample sizes can't be obtained are, simply, never performed - and as a result physics as a field grows in the direction of high-certianty.

Physicsts absolutely could be performing experiments with poorer statistics; it'd be cheaper, more advanced things would be done sooner, and we'd be having a replication crisis.

If the social sciences were willing to go a century without discovering anything exciting, they could achieve whatever level of certianty they wanted on their current budget. (At the expense of new discoveries.)

High certainty but that comes with second order issues: many ideas are untested, and the ideas that are turn into papers with 100s of authors. This stifles independent thinking.

Here's a modern experimental paper. Scroll down to the authors. You'll know it when you see it.

https://cds.cern.ch/record/2282544/files/arXiv:1709.05260.pd...

Your statement about huge numbers of authors (as well as the great number of theoretical papers that have to wait a very long time before being confirmed or denied) is true.

Wow the word-per-author ratio is close to 1. What's behind this padding?