I mostly agree with his answer, but what was the point of your question?
I want to know if for Linus Torvalds, currently there is no need to learn Assembly.
You should ask Linus Torvalds about that - why are you asking us? How would we know what Linus Torvalds thinks?
"Don't need to learn" doesn't mean "forbidden to learn"
And this is a hobby OS, so we write it in the language we want
How contributing to the KolibriOS writing code in Assembly?
You don't have to write in Assembly to contribute to KolibriOS - we support many other languages: http://diamond.kolibrios.org/hll/hll_eng.htm
But of course Assembly is the preferred language, and it's mandatory for kernel.
Please, I tried to edit the post
The Offtopic forum has limited edit capabilities for a reason - the messages that are here should better not exist at all, but because we are so kind, we are letting them stay, although limit the changes in them.