Steel has a load rating. Aluminum does not, unless you consider "zero" to be a rating. As long as you never exceed the max load rating for steel, it will remain as strong as the day you bought it. A bicycle frame made a century ago and ridden all day, every day, will still have 100% of it's strength as long as it's never been overloaded.
Aluminum forms microscopic cracks the moment ANY load is applied. So that same bicycle will have MUCH less strength. It will develop more cracks and becomes weaker every time the pedals go around, even if the rider is no bigger than a house cat.
This is why aluminum bikes are built with MUCH more material than needed. If they weren't, they would fail very soon. My aluminum frame might last 50 years for me, but might fail in 2 years with Lance Armstrong riding it. But make no mistake, it WILL fail in time. And when it fails, it will be sudden and catastrophic. Steel will usually just bend.
So with aluminum strap hardware, they are probably over-built and fine. But there will come a day, no matter how light their use has been, when they will fail with little or no warning. It might be tomorrow or it might be 500 years from now. But it is inevitable with aluminum.
This is why I only restore steel/cromo bikes. Too much liability with aluminum because there is no way to know how close it is to failure.
Just something to consider.