Go with the AM5 definitely, no doubt. Since you're gonna stick to the platform for at least 5 years, it simply does not make sense to get AM4.
Now The build does look pretty solid but I'm sure somebody else can suggest slightly better advice on that. My advise to you would be to sell the old not using parts + GPU and you will be able to get a much better GPU + possibly get more in the build too given you are not repurposing or giving someone the old build or that your budget already has that factored in.
