No Bambu keeps shutting down projects that bring any FOSS functionality to their ecosystem.

If this has to do with not wanting Bambu to monitor what you print, you could do is set up your own router (OPNsense, PFsense, OpenWRT) and put a VPN (tail scale, netbird) on it. Then you can set your printer to LAN in the router software, and with the VPN tunneling all your traffic through your network, your device will act as if it on the LAN. From there, you can send prints even out of the house without using their server side remote print functions.

I can only see three ways to get FOSS firmware on your printer:

1. If someone reverse engineers the firmware to create a FOSS version.
2. If the Software Freedom Conservancy, who recently raised funds to tackle Bambu Labs's license violations, finds a violation in BL firmware and succeeds in legally compelling BL to release the corresponding source code.
3. If you sell your BL printer and replace it with one that already has FOSS firmware.

No open open firmwares that I know of. I'm not 100% sure but I think other companies have caught up to bambu's ease of use. I'm planning on going with another company for my next machine. I'm waiting for multi color to get really good.