Yeah the childhood friend usually never wins in a love triangle, and judging from what I read so far (up to chapter 5) this manga is not seeking to buck the trend. It's only a matter of time before the childhood friend has to either confess his love only to be rejected, catches his crush with the other guy and deals with heartbreak, or slowly learn that he will never have his feelings returned and quietly accepts defeat. Or he goes yandere...
I hate when creators/writers put in a childhood friend simply to draw tension and possibly get sympathy from some readers, because you know it all will amount to a big ol pile of nothing.
It would one thing if the manga gave hints that maybe the childhood friend could win in the end, but that is not the case here.
You almost feel sorry for the childhood friend until you realize that the author is using the childhood friend trope to get an artificial reaction from the reader.
Give me a break! Shoujo writers, stop wasting our time with love triangles! Either focus on one romance, or at least try to make us believe that both romantic options are at least somewhat likely.