Egypt is a more normal country but I doubt they can match our arms production, both in quantity or quality. There's a reason they come to us. Part of it is we sweeten the deal with military aid so the money we give them is basically a gift card to be spent on our hardware so our companies can keep jobs and pumping out stuff. But its also because we're good at it.
Look, you have a point that if we didn't do it they would find someway to get their hands on arms but it would be a huge blow to these countries as they'd have to find less generous and effective benefactors. Israel for instance does not care that much about human rights, as evidenced by the fact that they're selling arms and training to Myanmar despite the human rights concerns there, and they have a very high tech weapons industry. But I'm just hard pressed to believe the gap left by a US restriction on arms sales to such countries could be filled quickly, it would take decades if it ever happened at all.