In my experience, it's really not pleasant having to work with logs that require a dedicated viewer compared to regular old text files I can use Unix commands available everywhere (`tail`, `head`, `wc` etc), with, i.e. not just on the server producing the logs, but also the device I'm viewing them on.

That said, I absolutely prefer UTC times in logfiles. I'd rather do some math every time than make wrong assumptions about the local timezone of the file even once. (Even correctly indicated local times are more annoying, since I have the math for the offset of my timezone to UTC memorized, but not that of every possible server time to mine.)