Unnecessary with the potential of ruining the job feels counter to the units role to me.
Its both frankly. Anytime ANYBODY complains about the vickers not suppressing people will chime up about how it kills more though! Perhaps the phrasing should be damage relative to suppression rate? At any rate the mg42 might do more damage as said but the vickers DEALS more damage and that contributes to the fuckery of it not doing its job.
When I was testing the MGs suppression speeds, I also tested the vickers.
Going into the tests, I had the same assumptions about the efficacy of the vickers, but the results surprised me and caused me to take a closer look at the vickers stats...
In NO test at 35(sightrange)+ meters did the vickers kill a model before suppressing. Now granted in an actual match you might run into a heavily damaged squad and the vickers could target that model on 20 hp or less and that would be problematic. But it does not seem to be an issue for most situations.
The whole "vickers doesn't suppress well because it kills models" seems an overexageration of the situation. The dps at 30m is 14, so to kill a full hp model in neutral cover with 1.0 RA, it'll take the vickers 5.7 seconds to kill it. The vickers has about 1.5 seconds to suppress at that range.
That said, the vickers does take roughly 40% longer to suppress a unit then the MG42 so it may just feel weak in comparison.