Traditionally you use a fuck ton of water in a giant pot but, really, that’s mainly so you can boil it harder without it boiling over so easily. The actual pasta comes out basically the same regardless of the amount of water.

What isn’t the same, though, is the water. And many pasta dishes call for adding some of the starchy pasta water as a thickener/emulsifier for sauces, so actually if you’re doing that you’re better off using less water as it’ll be more concentrated. And obviously less water boils faster.

For this reason many well regarded chefs have taken to cooking pasta in a wide flat pan with just enough water to cover it, at least for small quantities.

Serious eats has a good article: https://www.seriouseats.com/how-to-cook-pasta-salt-water-boiling-tips-the-food-lab