Why can't processor manufacturers increase the number of cores indefinitely? Do multi-core machines immediately grow in price?

Question

Processors

It would seem to change the connector socket and increase the number of cores to 16/32/64. Instead, manufacturers are trying to improve the technologies / frequencies at which processors operate. And for multi-core solutions require a lot of money. Why is this happening, what is the difficulty?
PS (I'm a teapot)

Answer 1

Not all tasks can be parallelized, the complexity of writing software increases significantly.

Answer 2

The cores cost money, and they are all needed (6/8/16) at a certain point in time very rarely, so there is no point in mass production.
For truly parallelized tasks, everyone has video cards

Answer 3

For the desktop, you don’t need more, and on the server everything will be parallelized by itself, with the exception of the database. So it goes.

Answer 4

Because users cannot increase the area of ​​the apartment indefinitely.