While that may be true, it’s a reasonable indicator of a person’s capacity to hear new information and then incorporate that into practice. If they’ve been told that they’re spelling a word wrong but then either can’t integrate that new knowledge or actively choose not to follow it, you’ve got someone who is either wilfully ignorant or lacks some capacity to integrate new information. Either that, or dyslexia.

Also, it genuinely depends on the work you do. My role has me writing up anywhere between 5-10,000 words worth of reports per day - proper spelling and grammar is key for competence in this role. I’ve seen reports where seemingly innocuous spelling mistakes completely change the meaning of text. Writing ‘can’ instead of ‘can’t’ and vice versa is an immediate example that comes to mind. I know this is an engineering grad, but clear communication is important in every role that includes managers, teams or other stakeholders.