As someone who works in a garage most of the day as a mechanicAs someone who has worked as a mechanic professionally, and now slings code for a living, I'll take a whack. You've put a set of brakes on a Chevy, you've put brakes on about all of them. Hell, put disc brakes on a car of any make, and you've got the general idea. I'm not saying it's not a tough job, hey, I've been there. But he nature of the work is different. What makes an alignment hard is not the same as what makes implementing this piece of code hard. What makes an alignment hard is frozen fasteners and having to go reference the manual because Mercedes decided that fifty years of prior art on caster adjustment just wasn't good enough for them, and invented their own. What makes this morning's software task difficult is that, though similar work has been done, no one has had to make it work quite like I need to do today (otherwise, I'd just buy something off the shelf). I'm making a new invention; not on the scale of the light bulb, but it's still new and there is no reference manual.
So, in the shop I can be fine with lots of noise and music as m 3/8" air ratchet backs out the brake caliper bolts. I don't need to concentrate on that much, I'm not going to bring the whole shop down if I screw it up. Pull the bolts, pull the caliper like I've done a hundred times. That Mercedes alignment, yeah, I might turn the radio down while I think about what I'm doing. But an oil change? Crank it up! (But even for an oil change, I recall having forgotten the drain bolt before putting in oil at least once.)
Software, OTOH, I need to mentally hold fleeting abstractions in my head. Someone droning on about the fscking SeaPigeons game on Sunday can easily break the tenuous grasp I had. I didn't even like being interrupted in the middle of a brake job if I were in the flow, but at least the brakes are right there in front of me when I have to go back to it. Not so with that algorithm for...oh, what the hell was it?
In summary, the nature of the work is quite different, such that mechanical work can be more interrupt-tolerant than software work.