This entire disagreement results from imprecise definitions. How can anyone claim to be right when they don't know precisely what must be true for them to be so?
For one, a distinction should be made between radiation in general and electromagnetic radiation. Electromagnetic radiation is composed of photons, which are massless particles. Other radiation is composed of massive particles. Since particle beams are massive, it makes sense that they would be deflected by "kinetic barriers" within the context of ME's narrative physics. Directed-energy weapons are the closest nonfictional counterpart to ME's "energy weapons." They are defined as weapons that transfer energy to a target without the use of a projectile, and this class of weapons includes weapons that use electromagnetic radiation, particle beams and sound as the means of energy transfer. There are still some who don't consider particle beams to be directed-energy weapons because they are technically extremely small projectiles. Particle beams and plasma are massive, so depending on their speed, they may or may not be deflected by a "kinetic barrier" in ME's context. One may ambigiously assign both of them to the class of "energy weapons," as most science fiction authors and others often do, and in this case they would not be deflected by "kinetic barriers," since this is what the canon states. However, in a technical sense, plasma weapons are not directed-energy weapons, and while many consider particle beams to be directed-energy weapons, this is not a universal consensus.
The participants of this thread have three tasks before them if they want to stop talking in circles and reach any sort of remotely rigorous conclusion in this sea of speculation:
1. Precisely define Mass Effect's class of weapons known as "energy weapons."
2. If the class of "energy weapons" is defined as equivalent to the class of directed-energy weapons, classify plasma weapons as directed-energy weapons or non-directed-energy weapons.
3. If the class of "energy weapons" is defined as equivalent to the class of directed-energy weapons, classify particle beam weapons as directed-energy weapons or non-directed-energy weapons.