I’ve been using Defraggler for years and have observed the completion time estimates swing wildly. Mine can oscillate between 15 minutes and 5 hours. I don’t pay much attention - just let it do its thing. Be sure to schedule at least one boot-time defrag also. Different versions of Defraggler have various options for free-space consolidation and moving large files to end of drive, also. But any kind of defrag is good for the stage you’re at.
Yes. As I said, it is back to normal for responsiveness. I am still boggled that the MS tool was obviously not doing its job very well.
Maybe I SHOULD get a Mac.
Surprised that has not been suggested.