None of what you describe here makes Mac "unusable". If your idea of "usability" is not needing to ever install extra software on a machine because it perfectly

None of what you describe here makes Mac "unusable". If your idea of "usability" is not needing to ever install extra software on a machine because it perfectly suits your particular niche set of demands for said "usability", then you are subscribing to an idea of usability that is probably out of sync with what most people would understand the word to mean (especially people on Hacker News who are more likely to tinker with their setups and want to customise things than most). Also Macs taking a more cautious approach to app access to your filesystem and accessibility privileges is a good thingTM actually?