I've had pretty good success with https://3dscannerapp.com - it's mostly intended for people with access to iDevices with LiDAR and an Apple Silicon Mac and in this combination can work completely offline by capturing via the iDevice and doing the processing on the Mac (using the system API for photogrammetry). AFAIK, there are also options for using just photos without LiDAR data and for cloud processing but I've never tried those.

I’d really like to use Polycam, but it’s unclear what features are free and what’s paid.

I’d be fine with paying for it, but it’s clear that they want to employ basic dark patterns and false advertising.