in any western russian neighbour vs. russia scenario they are frankly speaking not going to have much of an air force after the russian first strike anyway as happened to the ukrainian air force that only continues to barely exist because they receive new planes from other countries throughout the war. ukraine had a more powerful ground-based air defense grid than all of eastern europe combined and russia's has a more powerful one than all of europe combined and neither of them have proven to be impervious. imagine the shit state of some random euro country ad that need to protect those air bases with f-35. as an example poland had a few decent plane designs that made no impact in 1939 because the luftwaffe wiped them out on the first day on the ground.
Denmark