If you're selling all the .22lr you can produce, why would you make .17 or .22 WMR?
That all depends on where the bottlenecks are in ammo production (not to be confused with where specific cartridges are necked...
), and where the profits are.
If the primary bottleneck for rimfire ammo is the capacity of production lines, then it may not make sense to undertake the costs of temporarily repurposing production lines from .22WMR to .22LR, especially if the profit margin on .22WMR is approximately equal to (or greater than) that on .22LR. If nothing else, producing .22WMR or .17HMR ammo allows dealers to have something
on their rimfire ammo shelves. From what I've seen locally, the magnum rimfire cartridges seem to be routinely available, though not plentiful; .22LR, OTOH, is pretty scarce on the ground. This seems to back up my hypothesis that, for whatever reason, manufacturers haven't done much to repurpose production lines from magnum rimfire cartridges to .22LR.
OTOH, if the primary bottleneck for rimfire ammo is the availability of raw materials, it may make more sense to shift the allocation of raw materials to the most-profitable lines, whether .22LR or the various magnum rimfire cartridges. This matches what I've seen of .22LR ammo availability: when I see .22LR ammo on local shelves, it's more likely to be something along the lines of CCI Velocitor 50-round boxes (@$7.95/box), rather than 500-round bulk boxes (@can't find them, so a hypothetical price is exactly that).
Finally, I can't help but wonder whether Winchester's introduction of the new .17 Winchester Super Magnum
cartridge has affected the firm's production of .22LR and .22WMR rounds, just as demand is at a peak.