I think this is of course where the clause about not breaking the law comes in and I know Yoshi P came pretty hard on that one. I think people who actively seek ERP and advertise ERP venues put themselves at a greater risk and I think it's why YoshiP in an interview said to report them and they investigate. From my reading, there are venues that try to do a lot to self-police and try to avoid this from happening.
It's a risk outside of the online community as well or through dating apps and so on where people can lie about their age. A 16 year old could pull off the look of a 20 year old and I don't know many people in the real world who ask for ID from people they hook up with. How this is seen legally of course will vary from country to country. But for sure, do everything you can to mitigate that risk.
Honestly, I don't know how much of a risk there is, whether it's a perceived risk or an active one. I think the view from SE's side is do so at your own risk but you break the law of your country, you'll have actions taken against your account. I wouldn't want to curb people's engagement of these activities, especially if we're talking ERP as in writing erotica and not engaging in cybersex but at the same time, not want to see somebody vulnerable or unable to give consent being exploited. A scorched earth approach or banning it out right if anything could instead push the activities underground, which could make policing it worse especially as these communities self police and from reading comments last couple of days it sounds like people who run such events co-operate with GM's, so I suspect if in their self policing they find somebody doing something unsuitable, they can report it straight away (people are less inclined if they're worried they'll get banned too), so I imagine it probably works that way, but maybe there is better insight from somebody else. Either way, I think the GM's probably have the best data on this to moderate what's going on, particularly as I expect it's something people report a lot especially after YoshiP said "report it" and he said they have legal advisors for lots of different countries, so I expect what they are doing to moderate such activities probably is going to be the most appropriate.
I'd say if somebody's gonna do it, be confident the person you're engaging with is within the age of consent and they give consent. For me, given how I RP, I'd never ERP unless I know the person well enough and trust the person well enough & it made sense and worked within the context of the characters and their point in character development and story, because I am very keen on what's called the "In Character/Out Of Character" divide, I am not my characters, I write my characters. And some people self insert into their characters and I wouldn't want to do this kind of thing with somebody who's putting themselves into it and that can create all kinds of problems that I don't think are worth it. But I am not so prudish that I'd avoid writing something saucy if that's where things led to.