I realised this thread is almost half a year old but after 2 days of searching for answers on google, your situation seemed closest to mine. About 2 weeks ago, I migrated from a 2015 MBP (Intel Big Sur) to a 2021 MBP (M1 Sonoma). I have the exact same apps installed as my older mac, same network settings etc. Everything was running fine on my newer mac until I decided to pull up Forklift and it just wouldn't connect to the server, giving me a 'Host not found' error each time.
Puzzled, I decided to fire up my older macbook and Forklift just worked fine in there. So I knew the problem has to do with the new Macbook, but I just couldn’t locate the problem.
After messing with my firewall and DNS settings without much luck, I installed and tried a slew of other FTP clients. Some worked and some didn’t.
Apple’s own ‘Connect to Server’ feature failed.
Filezilla works only on FTP TLS but not with FTP, plus it crashed after some time
CloudMounter failed
Cyberduck works only on FTP
Commander One works only on FTP
Ironically, once Commander One connects to the server successfully, Forklift will be able to view the server and transfer the files. It just wouldn’t connect to the server with its own ‘Connect’ feature.