An annual London travel card is £2,568, and that only lets you travel around London. So why should be instead force people to buy something more expensive and less useful than a car?
Or 480€ if you get it trough your employer, which amounts to 40€ a month.
And very few people have a travelcard for the entire city, just you payg on your phone/watch/card for what you use. Unless you literally are crossing London 10 times a week an annual travel card is meaningless.
If your weekly travel sees you routinely hitting the cap then a travel card may represent better value.
The annual london travel card is much cheaper than operating a car. Not to mention public transport is london is an order of magnitude faster than car for most intra-city journeys.