The real reason that everyone should embrace/appreciate Linus' abrasiveness is this. Imagine what Linus' job as kernel boss would be like if people thought it was okay to submit crap-quality/untested patches to him (hint, it would be impossible). Imagine how long it would take for Linux kernel quality to dive off a cliff if quality were dependent wholly upon Linus' capacity to review and fix mistakes. Linus catching a cold unexpectedly could cause the whole thing to fall apart. Therefore, he needs, we all need for there to be some impetus to prevent folks from submitting crap.

Also, he isn't always abrasive, usually just if things don't go right.