I’ve never seen a snake in a tree, ever… I guess it’s a southern thing? You might be able to put a ring of pipe foam or similar below the netting, if it stuck out enough it might keep the snakes out.
After 20 years of trapping squirrels raccoons possums and groundhogs it’s been one of the biggest pains in maintaining my orchard. The traps need to be monitored regularly, they often fail and need re-tuning, if baited too frequently the birds learn to steal all the bait so you need to do it in waves, foxes try to drag away the traps so they always need to be well-secured, live traps for larger animals can catch foxes cats etc, disposing of larger animals in live traps is generally a pain, you can’t keep it up when out of town, etc. etc. What a massive pain!!! I usually trap three to five dozen squirrels a year and 3-5 larger animals. I’d sacrifice a couple snakes if I had to, I’d feel better about a killing a couple snakes than fifty squirrels.