Or rather doesn't have to make any sense. You can always come up with a different technofluff than BP that still enables for beam jamming if you wish.
Different technofluff than BP?
Preposterous!
Anyway, although Collie is very effective in its intended role - that of a destroyer killer, it would have no place in further warfare against the Shivans. The Second Incursion has taught the GTVA that whatever they can construct, the Shivans have something much bigger, nastier and more numerous just waiting beyond a node or two. That's why I like the BP approach, because it assumes that the GTVA aren't a bunch of fools.
However, against a non-Shivan foe, the Colossus could be actually quite useful, mostly in the psychological aspect. Just look at what would have happened in the BPverse should the Colossus survive. Not only is it a viable military asset that you can send in any time those pesky Solaris-class ships appear, but you can use it as a perfect bait. On any battlefield, it would become the prime target of any UEF attack - it may be outdated technologically, but all those beams and flak and fighters make it far too dangerous to be left alone, and the panicked captains would probably prioritise such a gigantic vessel, if only because it's huge. And while the bulk of UEF forces are occupied trying to deal with the Collie, which is sturdy enough to withstand their attacks for quite some time, you send in a Raynor or two to flank the forces and rip some frigates.
Of course this strategy would be only viable if the original Colossus had survived; I can find no reason for constructing another one.
