When most people speak of players online, or how dead it is now, they always compare the most online count they ever seen, with the generally quiet hours of the day, something that isn't exactly accurate or a reliable way to do such. Since the early days in FH, the most inactive hours has always been around 8:00-13:00 GMT/UTC time which also means around the early morning hours in "most" of the U.S. Time zones plays the biggest role in all this since the player base consists mostly of Americans and I don't think it would be a lie if I said they fill up at the very least 50% of the user base. From what I can understand too regarding Europeans(me included), some will take whatever chance they can to stay up a bit longer whenever the chance is given to be around when peak hours occur and most Americans log on. When I was able to and didn't have school or work pulling in me, my sleep pattern was suited to fit EST/EDT timezone rather than a European one, which means I'd stay up until 6am most of the nights.
Like the others above me I personally never saw the count go past 2000 players, but it was not uncommon to see it easily span past 1000 during peak hours which is most americans evenings when they're home from school or even work. I also recall very strongly that in the first half year or so when the game was up, during the quiet hours it was common to see the player count around 30-70 users online on regular weekdays.
A decline in users during peak hours has taken place though since it used to be more, but I feel like it's a rather reasonable/understandable change judging on the over all situation of the game. However some log on one morning and claiming the game is dead when they don't understand the importance and differences of time zones can get a bit amusing at times since the game is very alive and well for what it is and has been.
On a slightly different perspective.
A lot of "other" games out there live on hype and promises, treats for the players or just things to keep players occupied. FeralHeart was hyped to no end as well and people had their hopes up for a long time when it come to things to happen to this game, even new players joining today, the more you spend time into the game and community you realize that "what you can see is what you get". FeralHeart as a game and those taking care of it cannot promise anything plain off the bat, and just roleplaying, or sitting about as a lion talking to people might not be everyone's cup of tea(I know creation of mods and maps and what not exists but it's not as much "plainly playing" the game in my eyes). So that people come and go is not really a stranger aye? But as far as this player count goes, it's nothing out of the ordinary.