Besides the complete lack of any layers in Canada, the emergence and prevalence of guided munitions as a system to take out high value targets has really opened up the fact that there is a lack of a layer to deal with the small, inexpensive and swarming things that now fill the sky. As far back as Gulf War 1 most of our doctrine called for a an opening phase where we took out air defence systems so that our superior air power had full play. While once that might have been the role of aviation, special forces, specialized air delivered munitions and other long range deep strikes, we haven't changed our strategy much while other, smaller countries with smaller budgets, have become inventive.
My understanding is that GBAD which at best was set for a 2026 delivery has been pushed back substantially from that date.
I've said it before, we should at least lease some Avengers from the US so that we can revive our GBAD skills, knowledge and technical C&C base with these as training aids until the new systems come on line. By 2030 or whatever, there won't be an AD gunner left in the CAF.
Quite frankly looking backward at how we have squandered time and resources at preparing for the wrong type of conflict shedding capabilities and corporate knowledge left and right ever since we left our role in Europe, I see very little hope for the future. It's a good thing Canada has a very large moat around it.