What's up with the $BLOCK and $GMRX stuff that people randomly attach at the end of their tweets

It appears that people on Twitter are participating in discussions related to celebrity gossip, and they're ending their tweets with "$BLOCK" and "$GMRX." Clicking on one of these hyperlinks led you to posts discussing terms like "farming" and "boost," which seem to be related to blockchain currency.

The purpose of tagging "$BLOCK" and "$GMRX" in each comment seems to be to promote or discuss blockchain currencies or related topics within the context of celebrity gossip discussion.The use of the "$" symbol on Twitter, as in "$BLOCK" and "$GMRX," is different from hashtags (denoted by "#"). While hashtags categorize tweets and make them searchable within a specific topic or conversation, the "$" symbol followed by a term typically indicates a reference to a specific cryptocurrency or blockchain project. It's a way of signaling that the tweet is related to discussions about digital currencies or blockchain technology.

Answer: There's a classic financial scam called a "Pump and Dump", and this is a variant on that

The scam operates by artificially inflating the value of a financial asset, typically a stock or cryptocurrency, through hype and promotion. Once the scammer believes the asset's value has peaked, they sell off their own holdings for profit. This triggers a rapid decline in value as other investors attempt to sell, resulting in significant losses for those who bought in during the hype.

In the case of modern crypto scams, scammers utilize spamming tactics to promote their chosen cryptocurrency. By inundating social media platforms with cryptic tags, they pique curiosity and prompt individuals to search for more information. Even if only a small percentage of people actually invest, the sheer volume of attention generated ensures that a significant number of individuals fall for the scam. This approach requires less effort than traditional pump and dump schemes but still yields substantial profits for the scammer, while leaving many investors with worthless assets.

And what does the affix $ on twit/x do, and how does it differ from hashtags (#)?

Using the "$" symbol in the context of cryptocurrency scams is akin to mimicking legitimate stock symbols like "$AAPL" or "$MSFT." This tactic gives the scam a false sense of legitimacy, making it appear as if the cryptocurrency is comparable to established stocks.

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It's important to note that the intention behind spamming these hashtags isn't solely to get individuals to click on links. Rather, it's often part of a coordinated effort to make the tag trend on various platforms. These pump and dump schemes involve hundreds or even thousands of participants gathering in platforms like Discord. They agree to flood social media with tweets and posts containing the hashtags, sometimes even replying to unrelated posts to increase visibility.

However, behind the scenes, there's a smaller, more secretive group orchestrating the scam. They buy into the cryptocurrency before the larger group, then sell off their holdings once the value spikes due to the influx of buyers from the larger group. Many individuals in the larger group end up buying at the peak and suffering losses, leading to a constant turnover of participants joining and leaving these pump and dump groups in hopes of quick riches.