I disagree with this rather a lot. It's true that B5 had a somewhat shaky start, but no more so than most of the Star Trek shows
Well I was comparing it to Farscape and Battlestar Galactica, not the Treks, so that need not be a disagreement. However, I'll bite.
Confining oneself to the first four or five episodes (the context of the quote), any one of the Treks began with better acting and/or better production values and/or better writing from the outset... except TNG. But, yeah, TNG's first season was very painful and should not be used as a positive example of anything besides the most dramatic example of 'it gets better' known to sci-fi fandom.
DS9 in particular went in all guns blazing with stuff like "The Emissary", "Past Prologue" and "A Man Alone", which are all a cut above the B5 episodes I had been sitting through - not to mention a greater calibre of acting, production quality and writing in that case. Not instant classics - save maybe the pilot - but good, promising hours of TV that were leagues ahead of B5's first few hitters.
VOY may have begun less strongly but it still had superior production values, and I'll give the writing a pass for being about even if already plagued by technobabble. B5's problems are dire enough early on for VOY's flashier production and superior composition (orchestral wallpaper beats aggressively intrusive synth any day of the week).
Which leaves TOS. I guess that depends how you define what the first few episodes are - going by production order this no contest at all as "The Cage" kicks ass, takes names, and seems especially pertient now in our videogame age (basically, the Talosians died as a race because they were addicted to
World of Warcraft). Going by airing order, well, "Where No Man...", "The Naked Time", and yes "The Man Trap" are much more fun than B5's first few episodes.
And I like the kitschy sets!
The only one I really hate is the warehouse or whatever you call it in the down below area, the one with all the big crates that every week we head over to for the shoot out.