This isn’t written in stone for every tx but, that being said- lower vbytes should translate into lower fees. It’s more like 40% on the inputs, which matter way more… so 20% isn’t a crazy claim however this is also constrained inside of Phoenix wallet datasets based on their transactions.
It’s better to use an end of tree, provable branch to save size. The older p2wsh is less efficient in the size requirement and p2tr looks promising
nostr:note1uyeg093asfjjtzx7vkzva7wl7kt466l3qgcfymgaczxmnepmzqjseus2kp