If I open the QuickWKT plugin in QGIS, and choose "POINT (WKT)" from the combo box, and enter the text,
POINT (30 10)
I get a point at "null island" (0°N, 0°E). The entered WKT appears well-formed to me.
What's going wrong?
Note: this answer includes a screenshot of QuickWKT. My QuickWKT does not look like that; it looks like this:
It isn't clear to me as a user why I need to specify
POINT / etc. when the WKT itself encodes that. But the examples it has have those keywords, so I presume I'm supposed to enter them as well.