I suppose it's just another shift in the meta.
In 7th ed, Scatter lasers were the best, so everyone ran with them. Even against vehicles. BLs had some uses against tank heavy armies.
Now in 8th, there are a lot of wounds to chew through on many units that have become popular (tanks, monsters etc) so the BL has become a very important weapon to include in an army. In essence, the meta has shifted from SLs to BLs (and shuricans).
Scatter lasers are in many ways inferior to Shuriken cannons now, because the latter are assault type weaponry and do not suffer the penalty for moving. That, in addition to having the the "rend" ability, means the shurican has gain tremendous momentum. The caveat is the shorter range, which some people feel gives the SL an edge still. Damage-wise, however, the shurican is the preferred weapon for dealing with infantry now. If you run Saim-hann, putting SLs on bikes will likely yield better results than shuricans, however.
So to answer your question: you likely wouldn't take SCs (star cannons) or SLs these days, but shuricans are very much part of the meta because they are assault type and not heavy type. BLs are, as you have surmised, also part of the meta now given the re-design of multi-wounded units. As for the EML, it's essentially a worse weapon for tank hunting than the BL, and a worse choice for killing infantry than the shurican. It's also the most expensive weapon choice we have currently. It's advantage is that it's a more versatile weapon than either of those two.
That being said, I don't see myself ever taking an EML. I'll stick to grabbing BLs for units I want to hunt monsters and tanks, and shuricans for units I want to hunt infantry.