Are you implying that all Trade Unions are operated and run by Socialists? Because I can assure you that isn't the case, however I will concede that there could potentially be an issue that arises from said position in a hypothetical scenario, but I'm also wondering how often that would become a reality and how exceptions couldn't be made depending on the situation, for reasons that I'll hopefully explain in this post.
I'm not actually sure what you mean by your 2nd point, could you be more clear please? What are you talking about and how is it explicitly different from what I'm talking about? As a little thought experiment, say we achieved a Socialist Society and we voted to allocate Labour Time Credits to some proportion of Sex Work for individuals as we would with any other Socially Neccessary, but Unproductive Labour, would you still have a contention with the conception of the abolition of prostitution on these terms if no people would choose to perform said job or do you think that some people should be forced to do said things?
By the way, just so we're clear, I'm not actually decidedly of the position that Socialists can never support Prostitution, hence why I've elucidated some hypotheticals in my posts; my issue is that there seems to be a large amount of conflicting evidence on whether the Legalization of Prostitution in a Capitalist Economy and the way in which it is done ends up helping or harming Sex Workers, so I'm actually relatively unconvinced but I err on the side of caution given that I understand the vast majority of Sex Work undertaken is outside of the official economy and rests upon things like Trafficking & Organized Crime, often forcing people against their will into the line of work, and as a matter of Sexual Exploitation (which I agree, is an ethical concern mostly unrelated to Marxist Exploitation) I wish to minimize said harm.
I think that a lot of that isn't even neccessarily solved either through regulation or by our decision as Communists to "Support" Sex Workers whatever that may mean because most of these individuals wouldn't be directly affected by our support. As an aside it also concerns me that so many of those that advocate for things like full legalization are essentially self-employed people who aren't at any risk and aren't exploited either sexually or economically, I don't think I would be supportive of Sex Workers more generally if these people were the only ones that benefitted from any reforms or unionization, to the detriment of those who are essentially slaves.
As an example, in Germany there are Fully Legalized Brothels, and as I have myself been unemployed and used the services of the Jobcentre in the UK to claim unemployment benefits (JSA) in the past, some stories that I heard about concerned me. There are a certain amount of rules that you have to comply with when you get JSA, some of them are pretty obvious things like you can't earn over X from other means, you can't claim + have a job, you have to evidence your looking for work (this is fucking cancer, especially when they make you do it for 40 hours) but one thing that often happens is that you will be suggested to either go on a course for a potential job that usually involves some kind of work experience, and if you refuse, you can be penalized or have your benefits taken away from you. Now in Germany, there have been reports of this very same thing happening to women being threatened with potential penalization becasue they refused to apply or do work experience at one of these legalized brothels and this is something that genuinely concerns me, because if I were German that could be my mother or my sister, or even my brother if it were a gay brothel and the state could threaten to cut off the support available to them unless they agree to fuck strangers for a pittance, suffering a double exploitation. Now I know you will say, well we could simply make sure that the state doesn't touch those jobs or make those threats, but the reality is that in the UK jobcentres have been found to advertise and collaborate with all sorts of employers that they shouldn't have, and yet they do it anyway, even going so far as to in the past set up "Work Experience" whereby you would work a full time job for a period of X weeks just for payment of your benefits without any guarantee of a permanent job at the end of it!