lawman 1) If push to 2nd profile, does app take up twice the storage?
Yes, though how much storage depends on if you're only using the app in one profile there will be more storage consumed than on the profile where you do not use that app.
lawman If no, what happens to 2nd profile app if owner app is deleted? I tried deleting owner app, and a copy still stayed in 2nd profile (suggesting there are 2 copies at one point?)
Deleting the app in the Owner profile won't effect the 2nd profile.
lawman 3) A if (1) is no, how do we update app on 2nd profile? (chatgpt said both profiles disconnected so have to update on each separately)
How are you installing apps? (Google Play Store, Aurora, Accrescent, F-droid, Obtanium, manually by apk)
If you have the app store only installed in the owner profile, but the app on the 2nd profile, then you can only install the update from the Owner profile.
lawman 4) If (3) = update separately on 2nd profile, I don't understand benefit of pushing to 2nd profile, rather than just
Because there is no benefit to do it that way.
Note: Please stop using LLM's to get factual information without double checking actual sources, it can be easily swayed to a users opinion and provides incorrect information more than people realise.