Slow Internet Due to My Traffic Going to Apple at IP 17.248.243.4

I am running a late-2013 iMac with Catalina 10.15.7. The hard drive was going bad so I cloned the drive onto an external SSD and now boot the computer from that drive.

But afterwards my internet became very slow - like I/3 of the speed I should have. I checked with my service provider and he said Apple was taking all my bandwidth at IP address 17.248.243.4. I have not been doing any updates and I have checked the system with Malwarebytes and nothing was detected. I do have iCloud Drive activated but I have not heard of it affecting internet speeds in a negative way. This issue happens with both ethernet and wireless connection.

I chatted with Apple Tech Support and the person was well meaning but clueless.

Any idea what may be going on? This is about the strangest thing I have ever had happen with a computer..