Blizzaks are definitely not relegated to plowed roads or "less than 4 inches of snow". I can give plenty of examples with my Blizzak-equipped pickups, but a better example is with a Toyota Venza that we used to own. The first gen of the Venza was a big, slightly-lifted all-wheel-drive station wagon (they called it a crossover, but it was a station wagon. Ha.) It had 8.1 inches of ground clearance and we often towed our 12' x 101" open, 2-place ATV/snowmobile trailer with it rather than the pickup. Only used the pickup for the big trailers. We used that Venza to tow into snowmobile trailheads 5 miles in from the nearest plowed road which were often well over 12" inches deep so dragging the 8.1" belly the entire way with no worries of getting stuck. Since it was 101" wide deck, the deck was over wheels and so the wheels were inline with the Venza tracks, so trailer tires were not cutting their own path, which probably helped. People would always ask how we "got that thing back in here", but it was never even a question it would do it. Just decent winter tires. We would also take it trail driving in the 12"+ deep snow-covered forest service roads until the gates closed December 01 each year. Have plenty of stories with pickups equipped with them; pushing snow with the front bumper and grill. Definitely not for "snow less than 4 inches".
I'll also mention that some have the misunderstanding that the big tire voids (the open space between the lugs) increases traction in certain deep snow conditions because you can spin them and clear the snow. That is a concept that only applies to mud. All snow tires have higher void-to-tread ratios because the open space between lugs you want to hold snow, because 'snow sticks to snow' better than 'rubber sticks to snow'. You want the voids to fill with, and retain, snow because that snow will find good traction with the snow surface you are driving on. The harder/firmer the snow gets, the more sipes apply rather than snow-packed voids but the concept for sipes is similar, but just on a much smaller scale.
I suspect there are some specific snow depths and snow types where tires with larger voids (possibly even some of the all-terrain and mud terrain three-peaks rated tires) would be slightly better, but considering what Blizzaks have done on all my vehicles and the amount of deep snow I push, I feel it's an unlikely scenario for my particular use and that scenario is probably avoidable. For me, I feel it's better to choose the tire for the conditions I'll experience for the vast majority of my winter driving rather than a "possible" situation where a different tire might be better, but that tire would have worse traction for the rest of the winter miles.
That being said, once you choose to not run a three-peak all-terrain and have started to shop in the "soft-compound, dedicated winter tire" category, you are splitting hairs and really can't go wrong. If you want, reference the user satisfaction charts on Tirerack for that category, but no reason to overthink it. Pick any tire in that category, that meets your Gross Vehicle Weight Rating (be that C load range or an LT E load range), and run it.