Hello again !
The endgame of Warframe consists of farming "Kuva" for gambling re-rerolls of "Riven Mods" which you can get daily out of Sortie Missions if lucky ....... usually you get an Arcane Statue everyday....
So all you can do once you did all missions (1-3month) and reached ~MR 14-16, is the same crap over and over again.......
Kill fat ugly Kuva holding Trolls as Tenno with 100HP with strange attack while your out of your Warframe...
Then once you have a few thousand KUVA you need 900+ Kuva to re-roll a Riven Mod.
The lucky gambling slot machine results are 99% trash and your KUVA+wasted time are >= lost in eternity
(Warframe has nothing to offer after 2-3 month but the usual guild/friend/help new player support stuff. No endgame no Advanced skills... nothing)
Comments
WF was a game that DID HAVE a lot of promise at one time, however I am unsure what happened along the line but it seems to have become just another CASH SINK.
The latest expansion & several of the previous ones have brought a lot of new content into the game which is good but the game still suffers from BUGS it had come to light some 3 or 4 years ago! (WTH is going on with that crap?)
Now most of the players I started playing with back at the very start have left the game & only return briefly some days to say hello. they have also left because of the same things the OP has noted & the fact that the game is just way too repetitive.
So basically I wouldn't tell people not to try the game but I would tell them that it is one of those games that are 98% based on grinding & that are very repetitive.