If you do it yourself it can be so much cheaper, For example with a goal of about 20k spent This bundle gets you 12Kw of inverter output and 30Kwh of batteries for 11k. Then just grab two Of these solar panel pallets for 28Kw of panels. Or Alternatively go smaller with just one pallet and save a bit. Then ofc you will get the 30% federal tax credit on top of everything
Not everybody is going to want to do it themselves I get that, it's actually very easy and straightforward I posted another comment here up above that goes into more detail but honestly just about anyone could learn to do it it's not advanced electrical work by any stretch of the imagination.
Off-grid inverters bypass a LOT of that. And i should have been more clear on no backfeed. I would never recommend backfeed tbh. It comes with insane amounts of red tape, as you've noted, the equipment is also much more expensive for grid tie.
Off-grid inverters are basically a backup UPS on steroids. They accept grid as an input but don't feed back to it. They have far less regulation on their installations. Some places indeed you will still have some but usually you can get away with just having the final install inspected by a master electrician.