I don’t want to put words in their mouth or explain away what they said, so I will quote Wikipedia:

They said that their reference to the demonisation of rape concerned stereotypes surrounding perpetrators, arguing that rapists did not necessarily conform to a particular image and that such stereotypes could prevent victims from being believed, going on to explain that their reference to a spectrum concerned what they regarded as narrow legal and societal definitions of rape and sexual violence.

Which is based on a Telegraph article:

“The point I made about demonisation was that not all rapists fit a stereotype, and that all kinds of men can and do commit it.

“The vast majority of sexual violence is from men who the victims know personally. Victims should be believed regardless of who the perpetrator was, and rapists should be punished in the strongest terms.

“When talking about a spectrum I was making the point that laws often take a narrow definition of what rape and sexual violence is, which often allows it to continue without consequence. A full viewing of the interview clarifies this.

“In a country where rape has the lowest conviction rates of any crime, and reoffending continues, this is an urgent and important conversation we need to have in Scotland. Any suggestion that my statements minimise or excuse rape or sexual assault are deeply false and misleading.”

My personal impression would be this is getting at things like marital rape, but it’s not clarified further here, and I don’t have time to watch a full interview.

At face value though, all I get from this is they didn’t mean anything malicious and they are definitely not a rape apologist, which is what a lot of the discourse around the topic seems to suggest.

As a side note: they are non-binary and use they/them pronouns.