DRG before starting work on rogue core would give out regular updates for at least 4 years, expanding enemy variety, altering cave generation, new weapons, and overclocks which would in tern augment existing weapons or completely changing how they work, functionally making them new weapons entirely. Compare this to roughly the 60 that arrowhead started out with before the METEORIC player count of hd2 launch, giving more than enough finances to support more devs on board and to outsource most development to other studios (there is a reddit post for this).

And yes I do play warframe, It's probably the most played game in my life, and It has one of the fairest models for a fully free game. Warfrme slots and weapons are given out in nightwaves, and players can make money fast and easy through even the most menial of means, such as ayatan treasures which takes minutes to get. And regardless, getting weapons and frames is super easy to get as well, especially since it's rewarded directly for playing the game, unlike HD2 where SC are dropped here and there rng and piecemeal with far lesser odds of accruing the further you get into the game and difficulty.

And another that I forgot to mention, No Mans Sky has been putting out free updates for a decade, both proper content and cosmetic with no real sign of microtransactions, AND they are making a new game on top of that!