Work pass holders can absolutely marry Singaporeans. It just takes an extra step. I know you're trying to portray Singapore in the worst possible light, but false claims are not necessary to do so.
EP holders, being upper caste, can marry Singaporeans and I noted so above. WP holders require approval, which is granted or not on opaque grounds and frequently denied.
Anybody with experience of Singapore knows that despite the shining-libertarian-city facade, certain things are deliberately opaque. There are no "extra steps" for the first caste, EPs get processed blindingly fast.
But when "extra steps" are put in, they are circuit-breakers with the "intent to deny" and no explanation required. The "health measures" to protect Singapore during COVID were implemented by the Ministry of Manpower.
The "optics" as Singaporeans would say, are bad on the face of it. The reality is worse. I, with my November 2007 account, feel the need to use a sock-puppet on HN!