You said that airing down is more effective than a locker. I suggest you go diagonally up an incline with 2 wheels lifted with open diffs and whatever pressure you want, and I’ll do the same on highway pressures with my diffs locked.
Then you won't get very far irrespective of your driveline, neither will someone with open diffs & tyres aired down
When anyone looks through a long tunnel, all they see is a very small field of view at the end whilst ignoring everything at the side. The same goes for opinions.
If anyone thinks offroad performance is all about lockers/LSDs & nothing to do with tyre type or pressure, their field of view is very limited & so will be their offroading potential.
Conversely, if anyone thinks it's all about tyre pressures, they will be missing out on a lot of variety
Again, if anyone thinks offroading is all about big ruts & lifting wheels, their offroad experience is very limited & they should just be done with it, buy a 4wd & rip up the tracks on highway pressure & boast to their small d*****mates how they did abc track without airing down & in 2wd
There's a big world out there. It has tracks with ruts & boulders & fallen trees. It has tracks with mud & clay. Some tracks have a loose gravelly surface, like driving on ball bearings. Other tracks have super soft sand or deep snow. Some tracks are level, others super steep with a dangerous dropoff
The cold hard fact is having lockers/LSDs without decent offroad tyres properly aired down is going to severely limit offroad performance, just as having the best muddies aired down to 8psi & open diffs is going to do the same.
Having all 4 tyres locked together but spinning with no grip on a steep clay track will see you slide off the track & probably roll.
Having great tyres with excellent grip but open diffs on a rutted track will see you going nowhere, but at least you won't die.
So what is the solution? Well, both of course! Welcome to the age of enlightenment
