The issue here is that Mullenweg is on record everywhere (including on HN) saying that the "WP" is not the trademark problem; it's "Wordpress" and "WooCommerce".

But a cursory glance at Google results for "Wordpress hosting", "woocommerce hosting", or "managed wordpress hosting" will lead you to hundreds of results from a plethora of web hosting companies that have been doing this, many for more than a decade.

The Wordpress Foundation (that owns the "Wordpress" trademark) has not taken any legal action against any of these companies for precisely the same use it's accusing WPEngine of. A judge could well rule that they have not defended their trademark and this claim holds no water.