This topic has already been discussed multiple times. And why is this fraud? The definition of fraud is: "Fraud is an intentionally deceptive action designed to provide the perpetrator with an unlawful gain or to deny a right to a victim. "
In this case, Reddit is capitalist platform and it's trying to change its model so that its shareholders are happy.
Because they are unilaterally removing benefits that people have already paid for, and are explicitly stating that they will provide no refunds.
If you paid for a year of premium, a good chunk of the benefit has been the coins to buy awards.
After they get rid of both coins and awards, well, you have still paid for premium in advance, but it is now worth a fair bit less to some people.
Also bad, but more arguably in regards to the law, they are choosing to remove all past awards on posts and comments.
Which means that people who have bought coins (or premium to get coins) are having all of that undone, again, without any possibility of refund.
Arguably, this is much more problematic for people who had purchased coins, but who had not used them all before the announcement. Because that's taking the money, and then simply choosing not to provide the service that was paid for, while simultaneously stating that there will be no refunds.
You could try to argue that, well, they can use those coins up until they turn buying awards off... Except, well, one of the nice things about awards is that they last as long as the post or comment does.