One point of confusion here is that many of the so-called "ice roads" are built on frozen ground, rather than frozen lakes or other waterways. Northwest Territories calls them all "winter roads", even the now-permanently-closed winter road to Tuktoyaktuk which was almost all on ice.
The operating season for water crossings is shorter than on overland winter roads, though even the latter depends on the ground being frozen enough to support heavy loads. In NWT, not only are the overland winter roads closed in the summer, it is an "indictable offence" to try to drive them when they're not open. The mostly-overland winter road between Wrigley and Norman Wells has permanent bridges over waterways, so it can open when the waterways aren't frozen, but it's still closed most of the year. Conversion of that road to all-season, using most of the existing bridges, might be next on the winter road conversion agenda, once the new all-season road to Tuktoyaktuk is completed.
BTW, the president of Polar Industries, quoted in the NYT article, in recent years was one of the stars of "Ice Road Truckers". That TV show did its best to stretch the definition of "ice road", even including Alaska's Dalton Highway which is not only all-season but also partially paved (a fact IRT worked hard to hide from its viewers).