Daniela wrote very profoundly about how we are different than the western culture in that we give inherent value to deed and externals. We are physical. There is no escaping that. If we want to be something and live a higher standard it has to be with physical deeds. Thinking and believing won’t do the job.
Outside of Yiddishkeit a spiritual person is someone who thinks and preaches. We think as spiritual someone who acts out the Mitzvos.
Daniela’s other point, also very well stated, is that this is not the first thing that one may call ‘unfair’. A Baal Mum is Pasul for Avoda just like a Lulav is Pasul when it is split. We don’t say it is unfair because we don’t care about the Lulav, but it is the same mechanism at play. Just plain Pasul. If you feel bad for him that he became Pasul, well, I also do. I also feel bad for any Baal Mum, Kohen or not. I’m sure Hashem has Rachmanus on him, too.