You are the one who cannot articulate a single good reason why a worker who buys an expensive home (the only home they own and the one they actually live in) should automatically pay more tax because property is worth more.
They bought it with income that had already been taxed, paid Stamp Duty when they bought it, and may have spent decades paying a mortgage and mortgage interest. Take for example a person taking out a mortgage of £500k over 25 years at todays rate. They will pay a c.£500k on top of that, in interest, over the life of the mortgage. Jusr for the privilege of being able to get a mortgage. Is c£1m paid for a £500k house what we are calling a free ride?
And it doesn't matter how many times you say “proportionality” it doesn't actually answer the question: Proportional to what? Council Tax pays towards local services. A person living in a £2 million house does not necessarily consume ten times the local services of somebody living in a £200,000 house.
As for my other examples, they were not a diversion. You brought "easy ride" to the table. I spoke to your your claim about who is getting an “easy ride”.
If you really believe owning a more expensive home should create an additional tax liability, why don't you actually make the case for why. "Just because" the house is worth more is just regurgitating the current policy, it doesn't justify it or even make sense on the grounds you are arguing for it.