I've worked with a lot of developers from many different backgrounds: Chinese, Japanese, Vietnamese, Indian, Russian, Ukrainian, etc, etc and while even the thickest accent becomes easier to understand with prolonged exposure, I'd still much rather talk to someone without a strong accent when interviewing, especially over the phone.
If you're spending a significant percentage of your linguistic and abstract/symbolic brain processing just trying to figure out what the other person is saying to you (which can happen with particularly strong accents) it puts you at a big disadvantage for dealing with programming-related questions.
Huh? It's not something we have any control over. We don't understand them. Let me repeat that slowly: We. Don't. Understand them.
Also, note that this argument could be turned around in an instant: "If you want to work in the tech industry, don't distract others with your accent." Who is in the right about it? No one, I would argue. It just needs to be accepted that some portion of people have difficulty understanding some other portion of people. Don't make us feel like jerks for trying to clearly and precisely understand what is being asked.