Looks very plausible.
Apache keeps a good percentage, because a lot of legacy applications that revolve on the old PHP + Apache.
Also, we won't see servers that are behind a proxy (Nginx).
The same nodejs/ror/Java/spring applications revolve on its servers, a La tornado/puma/unicorn, but before them hung nginx. Not sure it's possible to determine. Moreover, it is considered a sign of good manners to turn off servertokens - and get the full the mystery of who gave us the content.