I know H5N1 had a high fatality rate before the current streak of diagnoses. If I'm reading (1) correctly, the death rate since 2022, for all known cases worldwide, is ~27%. Still bad, but a massive reduction from the 50%+ it had before. Current cases in the US are mild, according to (1).
I have little faith in pandemic response after COVID, but there are a few things to keep in mind:
1) We managed to shove a decade of viral research into 18 months due to COVID-19. We now have mRNA vaccines, which can be made far faster than other types and can be switched more easily in production. People (well, more people than before) are willing to mask if they're sick, at least in my anecdotal experience.
2) Flu has been the one that public health officials, doctors, virologists, etc. have been watching for years. If you had asked someone in those fields what their thoughts on COVID-19 were in 2015, they would have asked "what the hell's covid?", but would have been able to give you a fairly complete picture of what was happening with the different varieties of influenza. The enemy is known, to the point where rural villages in Southeast Asia can have people quarantined for the virus.
3) Again, recent cases in the Western world have been mild.
Disclaimer: I am not an MD, DO, MPH, PhD, or anything else of that nature. I have never claimed to be smart. I am a dude on the internet. Listen to smart people before you listen to me and my one source.