If we're already talking about misconceptions, WDVS should not be equated with Styrofoam.
You're right.
There is a range of other insulation materials that might be more appealing.
In the construction "building material shell + insulation shell," both are typically load-bearing for the plaster on their respective sides, for which foam board-shaped insulation materials are preferred. When installed between structural timbers, fiber mat-shaped insulation materials dominate. Furthermore, there are also loose fills that dominate as blown insulations where – usually during construction in the 1980s designed as air cavities – there were or are gaps between masonry shells. For concrete walls, loose fills are rarely used on the interior; mats or boards are common here.
For completeness, it should also be noted that there are building materials with insulation-filled hollow cores for (single- or multi-shell) masonry walls; as well as stone products with an integrated insulation foam layer.