Though from what I read, EA allegedly had zero input into Apex. That might be why it is becoming popular. I just tried Apex a few days ago, it was pretty fun.
"Of course, Titanfall 2’s disappointing sales aren’t as much to do with the nature of its content as much as it is about timing, and that’s entirely on EA. Sandwiching Titanfall 2 between Battlefield 1 and COD: Infinite Warfare hasn’t helped the game at all. Seriously, what were they thinking? Apparently, even the game’s producers were left in the dark behind the decision-making process."
Whilst the launch window for Titanfall 2 was pretty bad, I have a feeling that the multiplayer and longevity of the game would have suffered regardless.
The skill ceiling is too high for most players, and I feel that without the casual audience the playerbase would drop off as it has even without competition from the other shooters.
I started playing maybe 2 weeks after launch on pc, there weren't that many players. And I'd be running around looking for a titan and some solo pilot would be flying through the air parkouring and one shot no scope me. I wouldn't even see them. After about 30 minutes of getting murdered like that I just stopped playing. Luckily I didn't pay for the game. So yeah no real onboarding, people were way too good.