absolutely man! I like to draw from an example of a famous game known as World of Warcraft, i myself was NOT a player albeit a few hours in the trial to mess about but blizzard is an example of how a game company should react....
i did my college dissertation of video game economics and social impacts. after blizzard lost 50% of its monthly subcribers to WoW from 10mil down to 5mil - you know what they did? they paced up on expansions, making them better in value and bigger, they pushed more marketing and ultimately they made big changes, they made the game free to play up to level 20 and paved the way for growth in numbers again. Now of course this is just a comparison of the "effort".
when niantic lost 80% (as of April 2017) of its players what do they do? boi they dont even have a community management team or any like blog posts of promises to bait people to stay longer lmao
they dont seem to care, theres no tangible "action" i dont know maybe just a sense of: "hey we value you guys that remain, heres what to look forward to please stay LOL"