The tech community is known to have the most laid-back dressing policy you can find, in most organizations you find that software engineers exercise more liberty with what they choose to wear to work. While some deem it unfair its a topic worth addressing in a bid to foster understanding. Firstly unlike most jobs where you have to relate with clients (who may perceive you according to your physical appearance), most software engineers only have to relate with machines (that don't care what engineers look like).
More importantly, I dare say that the job of a software engineer exerts more consistent demand on the mind than most professions. Where the average profession can clock out for the day and head home to forget about the worries of work software engineers don't have that. There's always a problem to solve and the mind of a software engineer doesn't take breaks because it keeps processing alternative ways to solve the problem.
This means that software engineers are mostly too mentally exhausted to make low priority decisions like what clothes to wear. Personally, I let my hands pick my clothes most of the time. Usually the first clothes my hands touch are what I'm wearing.
A popular example of people who also agree with the way software engineers dress are Bill Gate and Mark Zuckerberg, it's no surprise that they were once software engineers. As the competition for competent software engineers increase organizations that prioritize results over aesthetics have learnt to look the other way (when it comes to software engineers) for the greater good.