Dear Schimon, writing on behalf of the modteam: Spam is an issue with which all open online venues have to struggle. Historically, the defenses implemented against spam have been sufficient. This has changed recently and iteam is working on understanding why that has changed and is looking into options to improve the situation without making the hurdles for new posters unreasonably high.
XMPP is being more and more exclusive to certain groups of people, while shunning others; and negligence, be it intentional or unintentional (e.g. this instance of undesired messages), is severely bad and suggests of deliberate sabotage by hostile elements within XSF, whoever those may be.
We are all committed to inclusion and diversity of the community, and we are open to constructive suggestions on how to become more inclusive. The XSF is driven by volunteers, on limited time and capacity. Suggesting that there are hostile elements within the XSF working against XMPP is a serious accusation, and nothing here supports it. Please abstain from further unfounded speculations of this sort. Georg (on behalf of modteam)