The effects didn't held up mostly due to the fact that the studio at the time thought it would be cheaper to redo the effects rather than store them on a proper master.
This sadly resulted in the effects (the purely CGI rendered scenes) being an interlaced crap fest on the DVD while the rest of show was in somewhat acceptable standard.
I've recently bought the boxset from Amazon for like 50 quid and rewatched it on a Sony 4K TV and the upscaling that Sony does made the show quite watchable still, not good but watchable.
That said the pre-remaster TNG releases are also an interlaced nightmare up to season 4 or 5.
I do agree with the rest B5 pretty much had to squeeze 2-3 seasons worth of content into Season 4 which meant that the 4th season ended up feeling rushed with most of the plot lines not getting the amount of effort they deserved considering the effort that was put into seeding them during the previous 3 years.
The 5th season under TNT was pretty much garbage, the last few episodes with the centaury falling under the influence of the Drakk were ok but honestly they should've just cut the entire Drakk plotline from S4 with the cancelation looming it would've saved us from having to watch Season 5, CTA and the horror that was Crusade.
B5 was a shining example of how a show can look like when the runners have the entire plot set up from the get go, too bad it's legacy got spoiled with Crusade, Legends on the Rangers, I'm not sure what happened my own personal opinion is that MJS probably needed much more help than he or the fans would admit.