HELP 10.15.6 update KILLED my iMac

Already did that (i.e. reset the SMC) *multiple* times. No joy.

If you are an Apple person (or if factory people read these threads) then the 10.15.6 update needs an update to the update.

Here is the whole sequence of events (that ultimately resolved itself (!?!)).

1. Successfully downloaded the 10.15.6 update (~3 GB)
2. the update itself began (black screen with Apple logo, "thermometer" showing progress..._
3. I left the machine alone for 3 hours.
4. I came back and it was unresponsive. Would not respond to the keyboard, or the mouse. Would not respond to the power button. It *was* consuming power (heat coming out of the vent).
5. I went through the 4 steps of troubleshooting, including disconnecting power (i.e. SMC reset), *multiple* times. No change.
6. After 30 minutes of trying various stuff, I gave up and left the room.
7. 15-30 minutes later (iI'm not sure exactly when..) the computer came alive *all by itself*. At that point it was not finished with the update yet. I let it continue to "cook" and it completed the update. By this time, a total of 4 hours had elapsed since the update was downloaded and the install had begun.
8. This is important. If you look on the support website, you will see that I am NOT the only person with this problem.

My guess is that there are one or more timing issues with this update, and there are one or more very large time-outs, that eventual time out when the race is trapped in the first place. Otherwise, I can't imagine why things are happening 3+ hours into the install. This is a 4 core 3.5GHz i5 proc, and an SSD. It never breaks a sweat, and on the rare occasion that I do a system reinstall (option-R), the whole process including the download completes in well under 1 hour.

There is something wrong with this 10.15.6 update.