Ryan 590 was another one where the aerodynamics might make a decent comparison. Cargo DC-9 with ice on top of the wings, barely made it off the ground but couldn't fly. There are some technical differences, its ice was inflight icing from the prior leg and it was very thin (although a pile of snow can always hide a thin layer of ice and/or have a thin layer at the wing's surface thaw and refreeze), the crew didn't get the airplane deiced (didn't think they needed to because they didn't see the accumulation on top of the wings/didn't look for it either- night, fatigue), and the accident report gets into some esoteric stuff about slatless airfoils (all but the smallest, oldest regional jets and business jets have slats nowadays).
It's hard to say exactly what would have happened, not without physically climbing on top of that wing in the picture and clearing it off down to the paint, soon after the picture was taken, to see everything. Exactly what though, it would have been bad.
When you know all the rules, regulations, and procedures, it's simply amazing that the guy in the truck holding the sprayer would be this grossly negligent. Or maybe he or she is just that stupid and it's a supervisory issue. It's sorta like if you were a tire jockey on your first day and in the interview it should have come out that you'd never picked up a wrench in your life- and the boss says go put that wheel back on that car but provides zero training, supervision, or watches what you're doing and turns the keys over to the customer.