That's the problem. They haven't done everything they could with F-Zero. And they've continuously neglected Donkey Kong the past few years. Donkey Kong Country's 25th anniversary was cast aside in favor of celebrating JUST ONE YEAR of Super Smash Bros. Ultimate, and this year it's Donkey Kong's 40th anniversary but Nintendo hasn't done shit about it.
I mean, there are rumors they've been working themselves on a game from the Mario Odyssey team. If that's true, then they've been doing stuff for years to prepare for it. I'm sure they will have something soon because it's a decently selling series.