Well as I explained the Set Production can be used for filtering in BPMs which is super handy for emails and integrations you want to stop from happening in dev systems.
The live designation I suppose you could use any way you want, but I’m guessing Epicor added it due to cloud tenants mostly for their own use in managing customers brought online. Especially if you bring more companies online in multi-company scenarios.
Help is useless in this case from a functionality standpoint, but use it as you like in BAQs or what have you.
Think of it as “Set Production” is system wide and “Is Live” is company wide. From there creativity in use is king.