It would not make sense for Tesla to do that (buy an ICE car company just to shut it down) this year, because they do not have enough spare cash to do that and it would be silly to reward the ICE shareholders with TSLA shares and dilute existing shareholders' value. On the other hand, I can see them doing that a few years down the road as an effective step in "accelerating the transition to sustainable transport". Once Tesla can produce enough cars to satisfy demand, then instead of dropping prices to create more demand, they might as well eliminate exterminate ICE companies.
All those ICE companies are going to suffer 1 of 2 fates:-
- Go bankrupt and close OR
- Start making only EVs and close a lot of dealerships.
Tesla can do more to accelerate the mission by building new factories, service and supercharging.
They can buy land, factory sites and equipment from failing ICE companies, a lot of that may soon be available at "fire sale" prices.
There are very few skilled workers and very little useful IP at legacy ICE companies, plant and equipment is useful especially at the right price. Tesla already has a great brand.
The Chinese may buy legacy ICE for the brands and dealership network. They need an effective way of marketing their EVs in the US and Europe. My guess is, mostly the Chinese will not want plant and equipment, they will prefer to build cars in China.
Another likely alternative is ICE market cluster via mergers into a large conglomeration of brands, that route also closes a lot of factories and dealerships.