I haven’t touched any single engine piston or similar in at least 5 years, I used to work as an instrument rating instructor before for 5 years or so. It does happen sometimes, ending up in visual moisture above the freezing level, especially at night where you aren’t always able to see the cloud layer. It isn’t good but I have found myself in icing conditions that way a couple of times. Past 5 years I haven’t had to worry about that, only flew proper aircraft since 
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Of course the potential is out there to ice up, stall and crash, its not impossible. The problem is that in MSFS every visual moisture encounter below 0 OAT immediately causes severe icing, within 2 seconds all windows are covered in frost, not only the forward windshields, also areas which will never accumulate ice in flight like cockpit side and cabin windows (frost on the windshields in flight, really Asobo?) and performance and handling is immediately adversely affected.
I even had a situation once where on the ground the aircraft iced up below 0C but without any visual moisture, visibility 5 km, no precipitation, it was impossible to take off, even at a way higher speed. Maybe there was some phantom snow, I found that even in snow, far below 0C icing forms on the aircraft in MSFS. For comparison, I flew in the morning and evening that day, same place in the real world, no icing on the ground at all.
Be honest guys, how often do you encounter ice accretion on the ground? Yes the aircraft might be covered in snow or ice from melting and subsequent refreezing of water after being parked outside overnight. But to actually see a clean airframe icing up like that? Only in active frost, freezing fog, rain or drizzle for a long period of time, definitely not with snow, it is so remote that you could easily drop the effect entirely. So there definitely is some tweaking to do, both visual and performance wise.
Something else interesting is that icing affects the stall warning and angle of attack sensors in MSFS. In real life icing has no effect on those (which is part of the danger). Yes the critical angle of attack is reduced with ice accretion but there is no way for the angle of attack sensor or stall vane to “know” or correct for this… Some more advanced aircraft might apply lower AOA threshold for stallwarning activation when there is ice on the ice detector or automatically whenever de/anti-icing is selected ON by the pilot, but this does not apply for a Cessna, Diamond 62 or TBM with a conventional stall warning vane. Maybe again something which Asobo finds will “confuse the gamer”, when stalling out of the air in icing conditions without warning.
By the way, flew the Kingair as well myself, 90/200 with Proline 21. Not as much experience as you obviously on that type but yes the Kingair is easily the most poorly modeled aircraft in MSFS, it does not handle like the real thing for even 1%. I think the Cessna 172 in MSFS comes closer to the real Kingair handling wise than the Kingair itself .