Even if you get 1 hit / day and that takes a long time to return, the ORM has failed your one customer. Inefficiency exists even at small scales with ORMs. If your developers don't know how to write SQL, let them learn. Or fire them if they won't.
ORMs are not inherently inefficient. And in my time I have seen plenty of n+1 style queries written with raw SQL.
No they are not. Have you measured this in a real-world application? This overhead is negligible compared to the cost of the query itself. And without an ORM you still have to load the data into some kind of objects or data structures before you pass it to presentation, you will just have to write the code yourself.
But yeah, lazy loading in a loop will kill performance. So don't do that.
You may be able to write faster code, but unless you are Donald Knuth, you can't guarantee that any custom code you write will always be faster than some library.
In other words, you have no idea what you're talking about.
Could you please (re-)read https://news.ycombinator.com/newsguidelines.html and not use this site that way? The idea here is to post civilly and substantively, or not at all.