I mean, the real reason is because the powers that be went from TNG to Voyager and let DS9 be run by mostly different people (Rick Berman’s meddling not withstanding). Hence also DS9 took actual risks and had real plot lines and story arcs, and Voyager got the truncated Year of Hell and that’s like it. Pretty much the same thing happened with Enterprise, with the people from Voyager running Enterprise for the first two seasons and a completely new set of people, led by Manny Coto, running Enterprise for the last two seasons that are much better received (except for the last episode, which Brannon Braga has since apologized for).
I mean, the real reason is because the powers that be went from TNG to Voyager and let DS9 be run by mostly different people (Rick Berman’s meddling not withstanding). Hence also DS9 took actual risks and had real plot lines and story arcs, and Voyager got the truncated Year of Hell and that’s like it. Pretty much the same thing happened with Enterprise, with the people from Voyager running Enterprise for the first two seasons and a completely new set of people, led by Manny Coto, running Enterprise for the last two seasons that are much better received (except for the last episode, which Brannon Braga has since apologized for).