That said, to be fair, some of the those episodes can get a little ham-handed or soap-boxy. For example, one of my favourite episodes is Far Beyond the Stars from DS9, where Sisko imagines he's a pulp writer in the 40s. Great episode, but I thought the actor went a little too overboard in the acting in his speech at the end. Some of the discussions are also a little too on the nose and feel like soap-boxing rather than real dialogue. Minor criticisms at best because I'll take those discussions over empty "lookit the pretty special effects!" stuff any day.
Similar to the movie District 9, which is a brilliant movie, but people thought it was too heavy-handed or on-the-nose in its allegory with South African apartheid. It's a fair criticism, but I'll take it over an empty action flick any day.