You can't say a first-time owner who has done their research and spent time around the breed they're looking for and tries to fit one into their lifestyle is worse off than someone who has owned 12 dogs of either the same breed or a similar breed, and then gets a dog that does not fit their lifestyle and the dog suffers because of that.
Well maybe maybe not...
With some breeds (malinois, cattle dogs, border collies too but not quite to the same extent, etc) I really think you absolutely NEED to spend time around lots of them before committing to owning one. I haven't had a BC yet but I am very familiar with the breed from being around so darn many of them. They're such a unique breed I think people really should spend that much time around them before bringing one home. On the other hand, I've only been around 4 malinois (and to be frank I ADORED all of them completely), but I don't feel as well versed in that breed at all. Research and reading only takes you so far. I researched and researched and settled on an Aussie for my bigger breed. That was until I was around them and training with both BCs and Aussies and realized that Aussies overwhelm me more than BCs for some reason.
I guess I'm having a hard time wondering how people get a lot of malinois (for example) experience without already being involved in sports or something of that sort. Most my experience with higher drive breeds has been because I'm already involved in dog sports and training with my current dogs.
Also of note, even if you've had 'easy' breeds, if you've had 12 or so (or less) in all likelihood you're not new to things like reactivity, dog aggression, etc. Now, you may not have had to deal with issues on the same scale, but you're not new to them. I've had 13 dogs and most have been easier breeds (BC/Collie, GSD/Golden, Lab, shelties, and papillons over the years.) In those 13 dogs I've seen most the big 'issues' you'd expect in dogs. So at any rate it's not all completely new territory to begin with. Would I expect to see aggression or another issue more strongly in other breeds? Yes, but at least I've lived with and dealt with it before so it's not completely foreign. Even if you have 12 of one breed, dogs vary a lot from individual to individual. Someone who has just had a Mia is probably a lot more dog savvy than someone who just had a Rose even though both their experience is 'owned one papillon'.
I just really hesitate to suggest some breeds to most people, even if they AREN'T new to owning dogs, let alone new dog owners.