If Sysop were running a business, he would not be fully compliant with business regulations. Sysop acts as an affiliate in many ways in that he is advertising products/surgeons and getting a cut of their profit. That must be disclosed in affiliate marketing. If an affiliate receives commission from selling another person's or business's products, that affiliate has to reveal this on his website in some form. That's why they have affiliate policies which show and describe the relationship between the affiliate (the one endorsing another company's products) and the company/business being endorsed by the affiliate. I do affiliate marketing myself - not for LLing - and you can be held legally liable for false statements through endorsement of other products due to truth in advertising laws. Now I'm not sure how this would apply to old forum , as I'm not sure it falls under an actual business, but if someone were to go after Sysop legally I wouldn't be surprised if he were found guilty of fraud.
Legal accountability would certainly make our lives easier in terms of being able to trust the recommendations to a greater degree. However I think in practice it would be incredibly complicated.
Consider Dr Salameh. If I were to get surgery with him:
1. I live in UK
2. SysOp is American
3. Dr Salameh is from Syria
4. Surgery carried out in Germany
5. old forum Servers are God knows where
Which jurisdiction does one take legal action with if complications arise? It is a legal nightmare!
DISCLAIMER: By all account Dr Salameh is a fine surgeon. I am simply using him for an example to consider.