Forget the videos.
The right thing to do is to have a single ground rod. To that ground rod you will connect your AC panel, the inverter ground screw, any other equipment ground connections, the metalic conduit the PV wires are in (inside or attached to any dwelling pv wires must be in metal conduit). Also run an EGC (extra grounding wire) from your grounding system to the panels. At the panels you ground the frames of the panels, the racking if it is metal, if it is all on a metal roof that gets grounded too. There can be only one.
Since there is no grid hookup the neutral ground bond is made in the AC panel of your house.
What you never attach to a grounding system is either pole of a battery or DC system, either leg of split-phase or single phase power.
The whole purpose of all of this is so ALL of the metal parts that you might touch are all at the same potential and there is no differential voltage to shock you. Tieing all of that to a ground rod means if you are standing barefoot outside and touch conduit or the ladder you have leaned against the roof you won't get shocked.
By attaching the panels and roof to the ground potential any lightning will travel to that ground rather than through the equipment.
It has nothing to do with anything the guy in the first video says.
For off-grid not being grounded that is to do with vehicles - planes, trains, boats, and automobiles. Any house, shack, shed, pig pen, doghouse, or other thing that is relatively permenant needs a grounding system.
You may not be getting any inspections so nobody is looking over your shoulder, but the best practices of the NEC are written for a reason. The guys that write that are smart guys that get paid to think about and argue about the code.