No, it's essentially a race on the number of users trying to get mined in the block. There is a hard limit to the number of transactions that can fit in a bloc

No, it's essentially a race on the number of users trying to get mined in the block. There is a hard limit to the number of transactions that can fit in a block (1MB, this is the block size). Users who want to get in the immediate next block will pay higher transaction fees to get in it. This raises the average transaction fee and causes others to raise their fee, too.