This is a very strong recommendation from Dr Darren, even if this recommendation is usually completely ignored.
In our workshop courses, one of the first tips is to load a starting style file into the MagicDraw® UML or Magic Cyber-Systems Engineer ® (Cameo Systems Modeler®) tools that has no colours other than black and white!
In the Webel SysML/MBSE course a typical b/w .stl
starting point style file is provided, or you can adapt the OMG b/w style. And yes, since nearly everyone ignores this advice anyway, you can very easily switch between Webel's style set and the familiar (but completely arbitrary) MagicDraw/Cameo default coloured styles.
You can easily switch back to the default colour & style set in the tool if you have for some reason indeed fallen in love with the MagicDraw/Cameo SysML symbol colours, just use Project Options > Symbol Style.
BTW: I love colour, and I have nothing against colour per se, it's just not always optimal for SysML diagramming. I even do colourful light synthesis art (using a device I designed using SysML) and colourful flower photography.