Feel free fastus to offer your observations…
For me, parkrun and running clubs are booming. Club track and field however is beyond crisis. There are a lack of athletes turning out in league and County champs u17 up, and apart from middle distance with bmc meetings, and wind assisted 100m/200m opens it is hard to see that athletes are just choosing different competitions.
Technical events only have traditional formats, so if you are noticing gaps, it is because the athletes don’t exist, rather than competing elsewhere.