It could, but then it wouldn't be bitcoin, it would be litecoin. Bitcoin is intentionally designed for confirmations to take 10 minutes. As more processing power is added to the network, the protocol adjusts the difficulty to ensure that it continues to take about 10 minutes per block.
It's strange that bitcoin got so much computing power and use it to solve a mathematical problem, while that power could be used to make transactions instantly, in my humble opinion.
Transactions are already made nearly instantly. Then, every ten minutes or so those almost instantly created transactions are collected together and a mathematical process that includes those transactions is worked out. It is the difficulty and slowness of this process that prevents an attacker from modifying past transactions in the blockchain.
Because this process is very difficult and takes the entirety of all bitcoin miners approximately 10 minutes to complete, it becomes pretty much impossible for any individual person who does not have as much processing power as total of all the miners on the network to replace any of those transactions with a new block of their own. Each new block contains a portion of the previous block in its mathematical process. Therefore, to change a transaction in the past, the attacker would have to be able to recreate valid blocks to replace all the past blocks back to the one with the transaction they want to replace faster than the rest of the miners are creating new blocks. Since the difficulty adjusts to keep the block creation near 10 minutes, this means that the attacker would have to maintain more processing power than the entire network for an extended time so that they could create each of these blocks before the rest of the network can.
The difficulty and slowness of the "mathematical problem" is the reason that bitcoin works. It is called "proof of work" and is used to prevent people from spending digital copies of the same output (coin) more than once.
