For a while I thought this was an unpopular opinion, but now I'm seeing more people agree. Relative to season 1-4, season 5 is extremely anti-climactic and at times even annoying (e.g. the looping Naomi transmission really got on my nerves). It's hard to believe season 6 will be the last after the complete disappointment season 5 has become.

Conversely I see hate for season 4, but I really liked it. I really love plot-lines around mysterious aliens or ancient technology. It's one of the reasons why Deep Space 9 and Babylon 5 are some of my favorite Sci-Fi series.