Not completely true.
I have seen 24 Spitfires at work together with a whole Balbo of others.
Then there is the new 190 and 262 project.......
BTW, BoB used a lot of models as well.
Not every WWII aviation movie needs to be about Spitfires.

You're never going to see something like a sky full of B-17s intercepted by a Geshwader of FW-190s without CGI.
Every year there are fewer and fewer flyable warbirds, due to airshow losses and people just not willing to risk their investment anymore.
Like you said even in the movie Battle of Britain they used RC controlled Stukas because there were no real ones.
Like you though I would rather see the real thing, I just don't see it being possible in most cases.
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