Is DDR5 worth it if I'm building a new PC now?

Yes, if you’re building a new system, go DDR5. The price gap with DDR4 is under 20% and shrinking, and you get 10-20% more performance in CPU-heavy tasks like gaming or video editing. DDR4 is a dead platform with limited upgrade paths, so DDR5 is the smarter buy for a PC meant to last 4-5 years.