Figure I'll throw my D&D 5E critique into the ring:
D&D, as discussed a lot in indie spheres on this site, isn't as simple of a game to learn as many people like to claim it is. It's only viewed as good for beginners because of WotC's and Hasbro's dominance over the TTRPG market making D&D 5E the most prevalent roleplaying game currently on the market.
The actual rules are rather complex to learn as a beginner, and are much more suited as someone's second or third game to learn rather than first. And... I don't think it's a GOOD form of complex.
D&D 5E feels complex in the sense that the system is bloated. Bloated with ideas from past editions that it doesn't fully understand, and hence doesn't know how to adapt and modify. This is different form a *good* form of complexity, which is a complexity that has been designed with game design intention and where the systems involved in the game work well together without being neglected.
My favourite current example of this is actually the system I'm currently working with for my module, @anim-ttrpgs's Eureka! Investigative Urban Fantasy (currently with a beta up on itchio).
Eureka, in comparison to D&D 5E, has a very cohesive idea of what it wants to achieve with combat, making the complexity that it does have feel very good to use, both from a player and GM standpoint. It aims for verisimilitude, it aims for something lethal and hard-hitting, and it achieves both of these very well, because it is very clear in its intention through its design and doesn't neglect its systems. The systems involved all have a purpose, and are not forgotten by the game they're in.
I dunno, working in Eureka has just got me thinking about this a lot. I'm someone who used to say I didn't like combat in TTRPGs back when I only played D&D, and now I find myself loving it and loving designing with it in mind because of systems like Eureka - and I think it comes down to that bloat. All the mechanics each D&D class has that remain from previous editions that don't seem cohesive with other classes. The seemingly unintentional imbalance between the martial and caster classes. The way D&D encounter design works. How various secondary systems in the game left behind from earlier editions - encumbrance, foraging, travel, light, resource management - exist but don't matter.
D&D 5E is bloated with misunderstood and poorly applied echoes of past editions, and left so by a team and publisher that seems to ignore game design in favour of what the investors and sales tell them. Which is quite a sorry look for the most prominent game on the market to have.
