It's a large saloon car, not a sports car. It doesn't suit a manual gearbox and in addition is very difficult to find with one. I can't remember when it changed but by late 2020 you only buy the 318i or the 318d with a manual gearbox, everything else was auto only. The only reason it existed in this car was to keep the price low. I think the 320d was available at first but only for about a year of production. Then it was removed from sale.
The automatic box is excellent and suits the car perfectly.
I'd estimate your chances of finding a car with a good specification and a manual gearbox is essentially zero. The fact you're looking at manuals probably explains why you're finding some of the earlier cars which didn't have the full digital dashboard and the later version of iDrive - this was standard on the M Sport and is, in my view, essential.
I enjoy driving a manual too, in the right car.
An 1800kg 4 cylinder diesel saloon is not the right car