Amazon and eBay and similar companies are not affected by this as they already collect (and maybe pay) taxes in all of these jurisdictions. The challenge is small companies, independent companies like mine that do not sale via Amazon, etc.
I am an online small business in Virginia. When my customer is in VA, I collect sales tax and file them monthly in VA. All other customers pay no sales tax. Currently, Washington and Pennsylvania also require me to collect and remit sales. So now, I guess I need to file 50 state tax forms every month? Agree to the ruling or not, this is a hefty burden.
I've never paid sales tax for any eBay purchase.