I believe it does have to do with the multi format laser selection. You can hear it motorizing something inside there. And a couple clicks as it decides what to do.
I do believe it has become slower over the years. Also, it's been quite a few years since I've used it, so I might be exaggerating just a little, but not much though. It's slow. Doesn't matter, because all that does, is the sound. And I can't wait to hear these few SACD discs I have again.