HI there FBNMRNO I understand that you have a question about the partition map of your hard drive and Id like to see if I could help with that. There could be a few different things occurring so I'd like to clarify a few things if i could. Since you mentioned that all your macs have this occurring its likely the case that you are viewing volumes within the container disk rather than partitions of the hard drive. More on that below. The next possibility, but i highly doubt it, could be that you are running a fusion drive that has split. If this is the case when you go into About this Mac > storage, you would see 2 hard drives, a large HDD and a smaller SSD. If this is the case then you can repair that by following these steps here, don't forget to back up your hard drive first tho.
If youre seeing Macintosh HD and Macintosh HD - Data then from within the disk utility app, then nothing is wrong with any of your macs, thats how its supposed to be formatted. If that is in fact the case, then your mac is using APFS which is significantly different than the previous files system. In APFS there are volumes inside container disks that are all free to share the space that the container disk is allotted. Partitions would have a set amount of space they could consume, moreover, data cannot flow across partitions like it can within the volumes in APFS. You'll see in disk utility on your mac running macOS Monterey after you click on view > show all devices, that the operating system has its own volume, and your data has another. Theres a lot more on this here, here and here.
I would suggest to stop erasing or deleting the volume because you will continue to relive the same ground hog day reinstall over and over. I hope this helps, feel free to ask any questions you have and ill check back later today to see if I can help!
