At the time of posting this question unauthenticated requests for Google Maps tiles work.
E.g. the following URL scheme would correctly load the tile shown below
Note that this is a styled tile as
s.e:l.i|p.v:off style directive turns icon visibility off. Without this directive a highway number sign would be visible.
This works as an XYZ tile layer in QGIS 3.
However setting custom colors would not work. For example to make the roads grey I would add an additional style directive
The modified URL scheme:
Produces the expected modified result.
However the corresponding XYZ Tile layer in QGIS seems to ignore this directive and still shows the roads white.
Is there a way to customize Google Maps tile colors in QGIS?