Great.
Thanks for all the advice.
The different models of tires are a bit confusing with different stickiness and casings.
I’ll try Schwalbe magic big betty
After tearing the side wall I’m ready to try a heavier casing.
My friend with the Focus has the Magic Mary 2.6's purple (softest, grippiest compound) and regular casing, with over 1000km on them and they are still good. In saying that, he did go mullet so probably put a new 27.5 on the rear 200-300km ago. I actually have his old bike/wheel here fixing it up and his old 29er Magic Mary is still good.
I got the Big Betty Orange stripe (2nd softest...so technically less grippy and more hard wearing) in the double down casing.
Some of the trails I ride are steep chunky rocks and I smash through them at speed. I have noticed tiny nicks on the sidewall where the sealant has worked but no rips or tears. My rear is losing more air now over the course of a week but it probably needs new sealant installed.
I do run cushcore which in the past has been a really pain to install on some wheels/tyres and I expected the Schwalbe Big Betty, with the double down casing, especially in a 2.4 to be really really really hard to to install. To my surprise, it was the easiest install I've done with cushcore.
I never used to be a believer in Cushcore inserts but after riding them for a while, they are truly worth it.
Initially I had one in the rear and eventually put a spare one in the front wheel and the difference in grip, dampening and feel was instantly noticeable. The bike was far more compliant, nicer to ride, grippier on the front. It also really helps with tyre shape of the sidewall regardless of pressure.
My friend with the Focus Sam2, cracked and dented his stock Novotec/Focus rims on a small rockroll (notoriously weak rims) which pushed the rim in about 50mm. Completely lost all air and managed to do one of the steepest, hardest trails at about 90% of normal speed just with the cushcore inside the tyre.