It is a huge crutch. Readability of those small details and elements and their tie to the environment is extremely important. Especially in architectural visualization. That’s why we have so many different AO techniques. Even ‘unbiased’ offline renderers have AO pass.
By the way, they backed AO not just for small details but also for bigger ones. You can even see on some buildings the AO cut off ‘stitches’ where elements with different baked AO passes (usually used as masks) connect to each other.
Switch to unlit / base color mode and you’ll see a lot more.