After many reports about this in the ETS phase, I thought the release of FMP 17 would have this handled, but alas it persists.
Delete Records, Replace, and other functions that formerly showed a progress bar to indicate what is happening and how long it will take no longer appear. In Mac OS, the dialog box remains present, a spinning beach ball appears, and one can only cross fingers and hope that the program has not become "non-responding".
I've come to experience a degree of trust that the requested action is indeed happening if I am patient enough to allow it to conclude without resorting to a force-quit. However, when I do force-quit and re-open the file, I always find that the requested action has indeed completed, but the dialog and spinning ball did not take note of this.
Perform the same exact action on the same exact file on the same exact server in FileMaker 16 and it works as expected.