To be expected actually. Most Sci-Fi shows get lost over time. Season 5 of Babylon 5 was totally useless. I couldn't even watch it because the show was basically over, and they were painfully stringing it along with another season. This what happens when you start a series with a definite goal. Once the goal is reached, the show is more or less over.
The same thing happened with the Andromeda series. The show ended in season 4 with the establishment of the Commonwealth and the destruction of the Magog world ship. Again, the producers went on to make a painful season 5 which added nothing to the storyline except the final episodes where they destroy the abyss which could have easily been incorporated in season 4. With Andromeda you can clearly see a descent into silliness starting about the middle of season 4 as the writers were obviously running out of ideas as to what to do with the show. Even the soundtrack becomes more silly like the A-Team would have than most Sci-Fi shows would have. Some of the episodes are more slapstick and smart quips than they are about anything else.
There is a main plot line which is eventually resolved. Once it is resolved the writers reach out into crazyland thinking that the more absurd and frankly 'weird' the show is, the more sci-fi-ness it has. You can see this effect even on Star Trek TNG when it got goofy and weird. The sun battling the moon, peptide cake, and the crew experiencing reverse evolution etc., or TNG would always default to a Holodeck episode or a Lwaxana Troi episode whenever they got bored or ran out of ideas.
It has meaning man, like dude, you just didn't understand the subtle nature of it, man. Nonsense. Those episodes are just garbage filler episodes, nothing more than that. They do nothing to advance the story.
Think of those days when many shows had 39 new episodes every season. Think of the writers desperately trying to come up with new ideas.
It seems many of the old westerns had similar plot devices:
the hero is going to be hanged by mistake and his family or friends have to save him,
or the hero has to stop an innocent person from being hanged.
the hero did somebody wrong during the Civil War or somewhere and somebody is seeking vengeance
the hero falls in love but the love interest contracts a terrible disease and dies ....or is killed defending the hero from the vengeance-seeking stranger.
the bank was or is being robbed and the hero has to stop the robbery or catch the robbers
the fast gun is in town and the hero must face down the fast gun.
The crooked banker or big man in town who controls everything and the hero takes him down and frees the townpeople.
All those.
If they didn't want to repeat those plot devices they could always go to the quicksand episodes. Yes, it seemed quicksand was everywhere in the west and people were constantly falling into the stuff and just barely getting out.
The Evil Twin or hero lookalike episodes were also fairly common.