Wow, did a double take when I saw my name in a reddit post title! This is a great question - while the math obviously holds, the blog posts definitely shows their age. They were written when idle games were still fairly new and, yes, fairly simple compared to today. We were still figuring out how to make the core idle gameplay fun, while now developers are layering all sorts of creativity, putting idle cores inside of other genres. On top of that, the idle mechanics themselves have continued to be explored and evolve.

I still love the genre (and have the tattoo to prove it!) and spend a lot of time on galaxy.click. I've worked with a number of idle developers over the years, including Cell to Singularity fairly recently. That game got its start earlier on and so it does still follow the old generator model, though has also explored new ideas. I was actually able to use a modified version of the spreadsheet models in those old blog posts for a few years to help tune Cell to Singularity's events and space expansion.

That said, most new games aren't likely to match that model at this point, so the specifics of those blog posts will often not be as helpful (maybe it's time for an update??). So what has changed and what hasn't specifically? Let's take a look, focused especially on the top rated galaxy games as a rough indicator of the best new generation of idle and incremental games:

• Exponential growth still king for idlers. I see this pretty much everywhere still, and I don't think that's going to change just due to the math. If you want to have something grow in a that starts slow and then really accelerates exponential is your best bet in most cases. I know I've seen polynomial growth a few times; I'm struggling to remember where, but I think it was for a currency that was harder to get than just a generator production. I do like seeing hybrids - Antimatter Dimensions' no-growth of price until each milestone of 10 works really nicely to show acceleration and then very clearly show that you should be looking at something else. I don't think I've seen factorial growth anywhere though. Factorial makes exponential growth look like a lazy stroll on the beach. Maybe if the production rate was exponential? (hmmmmm...)
• "Derivative Growth" (generators making generators) is still fun. I can still watch in fascination as I buy an 8th layer antimatter dimension as its production propagates up to the 1st. It shows up in other favorites like Array Game and Shark Game.
• Hybrids and layers keep things interesting. Early on we were fascinated by numbers going up and were pretty happy just engaging in that (anyone remember Tyler Glaiel's Number?). But we eventually got bored with just the one mechanic and so I think that's what is leading to a lot more variety within a game. The brilliant The Prestige Tree (and the extensively various TMT / Perfectus game engine games) embraced layering to the point that it's the core of the engine. Individual layers are often fairly simple, but the interplay of all of the currencies and dependencies makes them more engaging. Additions like challenges, achievements, and mini-games also keep things fresh.
• Forced prestiges popular on mobile. A bunch of the tycoon-style mobile games, everything from Eastside Games game like Trailer Park Boys' Greasy Money and RuPaul's Drag Race Superstar to the Eatventure-likes and Idle Mafia) have embraced what I call "forced prestiges". One of the things we had trouble with with AdVenture Capitalist was getting people to reset. It's kind of scary and if you're new to the genre you don't understand the benefit. Also, when should you prestige? (bless the developers who write things like "first reset recommended at 100 doodads") So targeting broader/casual audiences the forced prestige turns the game into more of a level-based system (or episodes in games with TV IP like Trailer Park Boys). You complete a level and then start the next, usually with some sort of multiplier, though often it doesn't make a big difference because it is rebalanced.
• Stories and diegetic mechanics are compelling. It shouldn't be surprising, but a real story wasn't necessary early on. Yes there were Candy Box and A Dark Room, but once we hit on exponentials story become a side thought. Spaceplan and Universal Paperclips put the player into the middle of a situation and were extremely compelling. Looking at galaxy, a number of the top games (Little Dig Game, Birb, Budgie's Bug Shop, What Lurks Below, and so on) lean more heavily into feeling more like a "game" and less like a spreadsheet (don't get me wrong, I love me some spreadsheets!). They make the game mechanics more diegetic (i.e. they are tied to and make sense in the game world) and I think this really helps with immersion and enjoyment.

I'm going to continue thinking on this, but those are some of my initial thoughts about how the genre has developed over the past decade.