Extending the 410 instead would be smarter as there's lots of traffic between Peel and Wasaga/Collingwood, proportionally more than Toronto I'd think, as tourists (and retirees making frequent trips to and from the GTA to visit family) tend to visit and retire to places closer to their sector of...
It was serious and far along in planning actually:
https://transittoronto.ca/subway/5114.shtml
Not to mention the original plan along the Finch hydro corridor.
Lines up with it perfectly though by the street grid.
Only reinforces the point of the name being chosen due to "confusion" of there being no Steeles station
They were opened before the "West" for corresponding stations on the later Spadina line was a thing. The change to "Pioneer Village" was almost for sure a "confusion" avoidance thing.