Dealerships charging very high markups should be addressed and stopped....but they do need to make a useful profit to be a viable business.
When dealerships are able to keep a useful stock of product for the customer so the customer can walk in, purchase, and drive away, that dealership has a useful purpose.
When the dealership is little more than a middle man who manages the transaction between customer and manufacturer, while not having anything in stock to purchase on site, that dealership ceases to provide a useful service because the purchase and wait for product is the same when the dealership is little more than a delivery site.
When dealerships are providing other services like maintenance, upgrades, parts, and special offerings they do serve a useful purpose beyond the selling of new and used cars.
With the recent situation giving rise to less, or no, new vehicle stock and long, long, long wait times for new vehicles, it can give the impression that dealerships are no longer required.
But we will ALWAYS want to try something like a car before buying.
Sit in seats, play with the knobs, feel if the car is generally comfortable for you....and even things as simple as, will I fit (some cars are very cramped) must be done in person........If there is no dealership and thus, no way to effectively try one on, things would be very much different in the car buying world.
This particular subject does correlate with another on this forum and it gives some insight into the desire to turn vehicle ownership into something akin to appliance ownership, rather than car ownership as we once knew it to be.