Shiny App Leaflet map doesn't filter correctly by year

Please consider if this is a shiny issue, or not.
If not, you can produce a script showing example filtering and displaying a leaflet in Rstudio (just without the shiny framework to interactively set params).

if this is really a shiny issue, then you should familiarise yourself with the shiny debugging and reprex guide
shiny debug and reprex

if its a more fundamental leaflet, or tidyverse issue, then the standard reprex guide should help you to demonstrate that to us and get effective help.

FAQ: How to do a minimal reproducible example ( reprex ) for beginners