Poor people can buy a car. Middle class families can buy 2 cars. Neither can buy 100 exotic cars. Is the purchase of each additional car going to increase the tax paid? Are exotic cars taxed more? You keep stating to use a power law formula but you're critically omitting what the inputs are to determine your tax rate. And now you've also admitted that assets determine your sales tax whereas you seemed to be arguing earlier that that wasn't the case when asked if the sales tax rate is dependent on your ability to hide assets.
> Otherwise, rich people who are hoarding assets will get taxed via land value taxes utilizing the same framework
Rich people hoard assets in all sorts of ways including collecting physical items which you can store where land is cheap if you wanted. That's why the income tax is effective - it's taxation at the moment the money changes hands / you've realized a gain.