This article is garbage but I'm a molecular biologist and the publication they're talking about is really neat.
The "ELI5 to the point of maybe reducing out the truth" way to explain it is that the researchers can add "flags" to proteins associated with immune responses that make cells pick them up and examine them. This is shown to work for allergins (so say, add a flag to peanut protein and the cells can look at it more closely, go "oh nvm this is fine" and stop freaking out about peanuts) as well as autoimmune diseases (where cells mistake other cells from the same body as potential threats).
It's not nearly to a treatment stage, but tbh this is one of the more exciting approaches I've seen, and I do similar research and thus read a lot of papers like this.
There's a lot of evidence that we are entering a biological "golden age" and we will discover a ton of amazing things very soon. It's worrysome that we still have to deal with instability in other parts of life (climate change, wealth inequality, political polarization) that might slow down the process of turning these discoveries into actual treatments we can use to make lives better...
Still, don't doubt everything you read! A lot of cool stuff is coming, the trick is getting it past the red tape