Upcycling devices like DOCSIS 3.0 MODEMs

I found some new in box MODEMs in storage and they are 3.0 DOCSIS. I was wondering how I could donate them to an ISP that still uses DOCSIS 3.0. I think several ISPs have switched to 3.1

Should I use the vendor recycling method and hope it stays out of a landfill?

Could sell them on FB Marketplace or Craigslist.

While most cable networks consist primarily of DOCSIS 3.0 devices, there’s an appreciable difference between an older 8 channel capable modem with 802.11n and a 16-32 channel capable modem with 802.11ac. Most ISPs I’ve worked with also like to standardize on a single vendor or a few models for ease of support. The modems certainly have value and I agree with Michael that the second hand market (for those that bring their own modem) might be the most appropriate place. I’ve also seen places like Goodwill take computer equipment like cable/dsl modems so that may be an option for you that keeps them out of a landfill.