It’s unexpected for resolving a “mongodb+srv://” URI to take 10 seconds. Sounds like a dns issue. Can you post the output of these commands?:
$ nslookup -type=SRV _mongodb._tcp.serverlessinstance0.abc123.mongodb.net -debug
$ nslookup -type=TXT serverlessinstance0.abc123.mongodb.net -debug
Until the dns problem can be fixed, you can go back to using the standard “mongodb://” connection string by finding it in the Atlas UI. You will need to select the earliest pymongo version in the “choose your driver” dropdown: