If you only take capital losses, you are capped at subtracting $3k from your total AGI. I’m not sure what you’re missing here. If you took a $50k capital loss, it would take 17 years to recognize it. Most people have income and capital gains/losses, and that’s why you want the losses to be subtracted from your income. You lost money.
Discussion
Example:
2020 I took 20k loss. I can offset 3k against income
2021 I took 10k cap gain. I can offset 3k against income, and then I can “consume” 10k of my cap losses (out of 20k) to offset the 10k gain
Simple
You are missing the point here. Your capital losses are capped at $3k per year against your income. Your capital gains are infinity. Waiting for “next year” to maybe get a chance at offsetting losses you took in the current year is preposterous.