So, we all how unrealistic the "lasers" of FreeSpace are... they emit light when passing through a vacuum, and they travel at
very subluminal speeds. It was unrealistic, but it was fun, and so were the tech descriptions (even though they didn't match the gameplay), so I was willing to accept the discrepancy. That said, I quite liked FS2's addition of "photon beam cannons" which actually behaved like
photon beams, crossing the whole field of engagement [nearly] instantaneously.
Some people (the Blue Planet team in particular) have retconned these as magnetically contained plasma weapons. Personally, I didn't much care for this.
Nonetheless, a while ago I came up with a "theory" which would allow the weapons to be all of these things as once: "magnetically contained plasma weapon", "slow-moving, light-emitting blob", and the surprising one: "laser".
Consider the GTW-66 Maxim Cannon. Although the tech title is "Cannon", the tech anim is "Tech_GTW-66_Maxim_Gun". It's named after the
Maxim Gun; according to the Wikipedia article "The Maxim gun was the first recoil-operated machine gun, invented by Sir Hiram Stevens Maxim in 1884. It has been called 'the weapon most associated with British imperial conquest'." We are not expected to believe that the GTW-66 Maxim Cannon is based on such archaic technology.
Similarly, consider how modern frigates are scarcely related to the "frigates" of the ships-of-the-line days.
What I propose is that sometime between now and when FreeSpace happens, the LASER becomes a historically significant weapon of war. Then later, that technology falls out of favor. Eventually (but still before the events of FreeSpace), someone makes a new class of magnetically-contained plasma weapon, and names it "laser" in honor of the historically significant weapon of wars past. This class of weapon becomes so immensely popular that all of its offshoots are called "lasers" as well.
Things not covered by this theory (but not exactly holes in it): the HL-7, which is described as a "Xaser" weapon; also "photon beam cannons"; there may be some FS1 tech descriptions I've neglected, as well.
Also it's entirely silly, as it's making up lore to patch other made-up lore to patch something I was just willing to accept as the devs not knowing what they were talking about.