I don't think safety sheets are a good way of discerning all ingredients in a product. GWax definitely is beeswax based. And the sheet doesn't mention that.
I have to agree with NeilC that the Safety Data Sheets do not contain a full list of the ingredients contained within the wax and cannot therefore be directly compared with one another.
Of the multiple types of wax I have the best any of them do in terms of listing the actual ingredients on the tin/container is "Beeswax proofing for all smooth leathers" (old Grangers G Wax tin) and "contains a blend of water based waxes" (Brasher Conditioning Cream) and
all the others say absolutely nothing about the actual ingredients.
It's a very competitive market and no doubt the actual formula of each wax will be a closely guarded commercial secret by the brands involved and by Grangers who manufacture the vast majority of them on behalf of those brands and are no doubt be subject to non-disclosure agreements.
It seems ninthace and sunnydale also have the cracking problem despite caring for their boots correctly so I’m afraid I don’t think G2EWS issue is down to poor care or maintenance.
Leather is by it's very nature a very tough material but it does have a limited lifespan and won't last forever. Regardless of the care and maintenance given all leather going through repeated wet and dry cycles will eventually start to harden and crack because the fibres within the leather can only stand so much flexing before they begin to deteriorate and the leather starts to crack and split apart at the flex points.
All that correct care and maintenance (including slowly drying the boots at a temperature between 15°C - 20°C) does is to extend the time before this unavoidable cracking happens.
This is Altberg's recommendation for drying their range of army boots but I'm sure the advice applies equally to their range of walking boots.
https://www.altberg.co.uk/military/drying-boots-out/All “nourish and protect”.
That's a slightly misleading marketing play on words and whilst it may be true to some extent the nourishment and protection required for normal day to day city/indoor leather footwear is vastly different to that required for outdoor wet weather leather hiking/walking footwear which is why using normal boot polish is unsuitable. It's just not up to the job. The phrase "you can lead a horse to water.........." comes to mind.