Well, I share your opinion on this. Time is great, we all have a choice from many beautiful machines, many well balanced machines and almost 4 new titles per year. This is blowing my mind as well.
I think the older machines are built with another mindset than the newer machines. If I look at my own collection I only have the end 80's/begin 90's machines. I love my TZ, I love my BOP, I love my FH. Owned a POTC and that left after one year. I loved the machine for a year and now it's over. Look at the new sterns, all lovely machines, deep rulesets, but are exchanging owners more often than I change my underwear. (Yeah, that's actually incorrect, or is it?? )
What I absolutely love is the amount of choice we've got at this moment. If you like system-11, eey, grab a system-11. If you like the new sterns, eey, get a stern. If you're a girl, eey, fix yourself up with a Wizard of Oz. (Just joking guys, djeez...)
What has changed is the experience, in the 90's you could go out and enjoy pinball with your friends in a bar. Now it is at somebody's house, still with friends. Back in the day (with limited funds) I wasn't able to work on my skills. Now, owning a pinball machine (actually I own 6 at this moment), I am able to work on my skills. That actually has the pleasant side effect that a much deeper ruleset is needed to keep me interested. On the other hand I sometimes want to play some quick pinball and like the fact that sys11 had a limited ruleset. Just enjoy some pinball and forget the daily crapp we all have to put up with.
So, in conclusion, the golden era of pinball seems to be now AND in the early 90's. The experience has changed, we now have more choice. Funfactor is the same amount but fun is different. So I count myself lucky to be able to experience both.