Game console controllers have had pressure-sensitive buttons for a long time. Generally, they don't work well since there's no useful tactile feedback. You're never entirely sure how hard you're actually pushing. As a result of this, people often use much more force than necessary to ensure that they have pushed the key all the way, which leads to ergonomic problems.
The video shows one useful application of the technology: It could be used to determine whether keys were pressed intentionally, or by accident.
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