Its not a rare thing unfortunately the UK dealers are pretty lazy! It will be down to lack of use it throws up every possible error message when the battery is not properly charged.Indeed I consulted your useful post I remembered it being posted when I was first looking at the cars so thank you for that, I just assumed it would be a rare thing and not a concern.
Let's hope it is just lack of use.
I will use it daily but what happens when you go on holiday and say park it at the airport or something
Someone who works on an oil rig off scotland's coast parks his in a car park for 3 weeks and says it usually starts first time! If its used regular & in good condition should be fine I mean its a ridiculous issue but the RS R&D engineers are mainly working on new RS projects in France now (RS EVO most likely) so its not ever going to be addressed as it looks like 2021 is the last RS pure I.C.E year
See how it goes maybe buy a battery booster just in case to keep in the boot (Renault should supply this but they have not admitted its an issue as the car needs to be used regular!).