If I were to guess, this is basically only an update that applies to Apple Pc's that have Intel related hardware. Ever since the Radeon Pro/M Chips, intel cores have been obsolete on the hardware side of things. Intels are kind of hard to come by if you're a newer Mac user; and if you are, you have nothing to worry about (unless you bought your Mac/iOS second hand). You really don't need to worry about it. It's about the graphical interface of SoulSeek. Intel graphics are a widely known, widely supported GPU interface, but thanks to the sudden changes from Mac, intel is a thing of the past in terms of integrated graphics support infrastructure.
Again; if you don't have an intel-Mac, don't worry about it. But I have a feeling soulseek is smart enough to know you have one.
If you do, you're fine, just expect less and less graphical support updates in the future, as it's already been out-dated for the last 4-5 years of Mac computers. It sucks, but it is what it is.