The fact that we can still play the original Garden Warfare, despite it now being 7 years old and having 2 sequels (BfN may not exactly be GW3, but it certainly is meant to be a sequel of some form), and get matches even on PC which has the lowest population (mostly TT of course), is actually amazing. It also proves to EA that there is an audience for the games, which translates into purchases if done right.
I haven't seen all the sales figures but this part of the PvZ franchise has definitely done well. Some YouTubers like Wolfy and Zero have built their YouTube channels almost solely on the GW games, and ZachScott certainly has done well in this regard.
There's a long video discussing the games and their future that features a lot of prominent YouTubers:
I watched this awhile ago and I think it outlines the situation very well. This series of game has touched kids, families, young adults, and old farts like me. I still login to at least GW2 and BfN everyday, even if only for a little bit (although last night was in GW2 for a long time as I had to finish the 'Complete 15 games of Gnome Bomb' epic quest and that takes awhile, even with no bots), but let's be honest, we need a new game with more content, new stuff to do and unlock, and lacks the issues that we see in the current games, much as I love them, they aren't perfect.
Considering how many people love PvZ, it makes more sense from the perspective of EA to make a new game, maybe a bit later than we'd like, but someday in the near future, to make a new shooter. I just hope it is sooner rather than later, has crossplay, is well supported, and brings back what we love while also adding some new stuff to do and enjoy as well.