Name a TCG that is of similar or higher complexity. The main ones are Magic, Pokemon, YGO, and Hearthstone, and they're all of much lower base complexity.
I don't play that many TCG-style games but I can name you just a couple:
Android Netrunner: featured asymmetric play (each player is playing a different way, the decks between each side are incompatible), and each side had like 5-6 different types of cards in the deck, and had to build an economy system through card powers (not just playing lands or gaining mana). It's way more complex and has a pretty diehard fanbase at this point.
Star Wars Destiny: You have character cards that work in tandem with customized dice, as well as a deck of other cards that supplement those characters through assist characters, weapons, powerups, one-shot abilities, etc. The footprint of this game looks light but it has a fairly meaty decision-space that can be as complex as Artifact's.
Then there are card games that people play a lot, with a lot more complexity than Artifact:
Race for the Galaxy: The game's iconography alone puts a lot of people off from touching this game. Getting past that, you still find a pretty steep learning curve as you learn how to maximize the game's turns. But people who dive into it play it many, many times (like hundreds, or thousands of times). This card game has been around for over a decade now, with several expansions. It even has an app version that is like $6.99, and people buy it!
Arkham Horror LCG: This is based on the Lord of the Rings LCG, both of which are very TCG-like in that you construct a deck ahead of time, but they are coop (or solo) against the game. It is very popular, despite taking a fair amount of time to play and features a fair more complexity and difficulty. It also costs a lot of money. People love it!
I mean this list is by no means exhaustive, it's but a small sample, but the point is there really is a market with a strong appetite for card games with more to them than Magic/Pokemon/Yugioh, and with a different business model. That's not just conjecture, there's proof that these games constantly come out and get reprinted.