I have a 2019 21.5 iMac and have recently upgraded to Ventura. The Mac has become rather sluggish especially when loading browsers, so I ran Onyx. I received a message saying that I had a problem that could be resolved by booting up in recovery and using disk utility to run first aid. I did this and got an all clear but the machine is still slow and when I run Onyx I get the same message. I thought my system might be corrupted to I booted to recovery and attempted to reinstall Ventura but received an error message after about an hour saying the installation could not be completed. What should I do next?