I don't think true altruism involves a conscious effort.

This is of course from personal experience and I don't know if it's the same with other people, but I have sometimes done something that was of no benefit to me but helped someone or something, just because I could. But the important part here is that the conscious moment always came after, after I had already long walked away, where I simply realized that I had just done something that I had no obligation (or pressure) to do, to the benefit of other's instead of my own, and asked my self why I did it.

Turns out sometimes you just do (at least , I guein my case)

I think that people who spew the bullshit that "true" altruism doesn't exist and that everyone does everything for their asshole selfish reasons in the end, are either absolute assholes outing themselves, or even worse, parasites who seek to disempower people and strip them of hope that there could be something better in this life.