Let me preface this with I enjoy classic movies and can fully appreciate the GMR being a nod to classic Hollywood, so I totally get your point and can agree; however, the GMR isn't entirely focused around the Golden Era (1920-1960). There are handfuls of movies represented both on the ride (Man with No Name, Alien, Raiders) and in the video finale that are more recent/modern. At some point, movies made in the 80s are going to fall under the label of classic, right? Why not add to the GMR to include more recent hits that are turning into classics? TCM themselves show plenty of 60s, 70s, and at times, 80s movies. I mean, does ANYONE who goes on the ride know what Footlight Parade is? I know I wouldn't be upset if that was pulled in lieu of another classic movie scene. Perhaps others feel the same? Even if they didn't include more recent films, there are still a plethora of highly regarded classics absent from the ride. Sadly, licensing rights would probably make it nigh impossible for a lot of films, regardless of their era, to be represented in the ride.
In regards to the last part of your post...being part of the new generation...I do like thrill rides. A lot. I can, however, fully appreciate what a ride like the GMR brings to the table. I mean, if your options were to see it re-done to include more late 60s and 70s films vs shutting it down all together, wouldn't you rather the former?