FWIW, I'd found https://www.geocod.io/ to be a good service a couple years back. They sponsored some conferences I went to, and I needed some geocoding->timezone info. IIRC, at the time, it was $5/month which covered everything we needed. Dunno if that's eye-watering or not.

Seems to have changed pricing a bit since. The 'pay as you go' model now has 2500 API calls/day for free, and $1/2000 API calls after that. My needs never grew in to needing much more than what we hit for that $5/month, so I can't vouch for their service at a large scale, but I enjoyed using it.

No affiliation just a happy former customer.