That wouldn’t help I don’t think. I’ve had very small holes in a faraday cage results in rf leaks - slots thinner than a credit card.

I see what you are saying and understand that problem but I was picturing something like this type of can from Home Depot:

https://www.homedepot.com/p/Behrens-31-Gal-Galvanized-Steel-...

I use these as planters for my orchard fruit and nut trees. They have no open holes. I have to drill the bottoms or side to add drainage so that the trees don't drown.