Obviously, the main benefit of raising your prices is that you get paid more per client. Over time, as you gain more skill and experience, it makes perfect sense to consider raising your freelancing rates. No client expects you to keep your rates the same forever. As inflation sends prices higher, those effects also impact services. If you want to improve your income effectively, at some point you will need to raise your rates as a freelancer.
Setting freelance rates is a complicated business. It is even tougher to raise rates. This is why it can help to raise them on new clients and projects first. You may feel less rude when doing it with a new client, than someone you have been working with for years. Starting out with new clients and projects can give you a pretty good idea of what others are willing to pay for your expertise, and it can help you tweak your offerings to find out what value-added items clients are willing to pay for.