As someone looking at purchasing one, I do find these threads interesting.
The challenge is to navigate between genuine concerns vs personal perception of what is acceptable.
I'm coming at this from a position of owning both classic Defenders (a few purchased new via JLR, the last one being a 2015 90) as well as owning other vehicles produced by small volume manufacturers, as well as classic cars (anything pre-80s).
Discounting the lack of jacket, which I view as an annoyance rather than an issue with the vehicle, then it boils down to quality issues / control.
Reading this forum, some owners seem to have had a problem with water ingress into the footwells - not a deal breaker but a frustration. One owner attributes it to a kink in the door seal, which fixing seems to have rectified the fault. As for the others, not sure whether they have gotten to the bottom of what is causing the problem and resolved it? If this is a reasonably common issue both Ineos and the ADs need to get on top of it because it will stop new customers from committing; given the available cars, I'd suggest the lacklustre reviews, which all seem to focus on: poor mgp, steering feel, wheel turns lock to lock and general below average build quality (including RHD driver's footwell hump) are all contributing to this. Lots of negative forum posts, vlogs and social media posts won't make it better.
I worked closely with an established small volume UK car manufacturer and they always (still do) had (have) quality issues; rarely things that would strand a customer but things that would niggle and frustrate. Price point was/is not dissimilar to the Grenadier. The worst problems stemmed from new to the brand owners because they compared their new car to Porsche, Mercedes, Audi, etc etc. The moment you did that, the downward trajectory in satisfaction was set. My advice, after studying the situation for years and across a broad spectrum of owners, was that the manufacturer needed to better educate dealers when it came to new owners and set realistic expectations. In other words: 'this vehicle may not be perfect from new but if there are issues, they will be addressed and rectified at the first, break-in, service.' Of course, this can be delivered more eloquently than my paraphrase but you get the point.
HOWEVER, there was always two issues: firstly, no sales person wants to be honest in the manner required because it could stop a sale. Secondly, even if the salesperson does try to bring expectations in line with reality, the possible owner may have their rose tinted glasses on and when issues occur the response will be 'you said there may be issues BUT I didn't think they would be this 'bad'!
Needless to say, it went nowhere.
Reading this forum, I hope Ineos isn't falling into the same trap - over promising and under delivering, made worse by unrealistic expectations and lack of realistic ones being voiced at purchase and delivery stage.
I will also add that I am a firm believer that people don't remember problems, they remember how they were resolved or not... and if comms are poor at dealer / head office level, this is simply going to exacerbate all of the above.