I frequently (almost daily) am challenged on "why should I seal my pavers?". On a typical day I take or make a total of 50 phone calls. I spend the majority of them trying to educate someone on why its important to seal their pavers.
From my perspective having to convince someone in words is a little frustrating. All you would need to do is follow me on a days journey and see the thousands of people who call us for help in restoring their old, faded, worn out pavers. Those same customers are typically the ones who challenge such a notion as to invest in protecting them. At a simple glance you can see damage, wear and stains that aren't reversible. Most often to surfaces less than 7-8 years of age or even newer. Almost without fail there are usually numerous areas with catastrophic structural issues. All of this would have been prevented if they initially invested a small portion of the overall cost of the installation to sealing them.
Even if someone is disappointed with the appearance of their pavers a year or two after sealing them, they must understand that the overall point is to protect them. The natural beauty of pavers whether enhanced or not will not stay for long if a quality coating isn't applied. The Florida sun and rain will wear the very thin decorative surface away within a year or two. Once that happens you tend to get mold and algae growing deep into the stone thus requiring harsher pressure cleaning. The cycle begins.
Going back to the people who I visit daily with pavers that are in rough shape. 9 out of 10 of them admit that in hindsight they made a mistake not sealing them. This of course only after spending 20 minutes educating them on exactly why they are having the issues they have and that NO, its not able to be reversed.
The bottom line is that sealing your pavers from the get go or even a year later will put you on the track to have that large investment stay beautiful for decades if you so choose to stay in the cycle. If not, just ask yourself if your okay with spending the same amount of money you just did replacing them 8 years from now.
If you have older pavers already its not too late to seal. Yes, they can't be "fixed". They won't look new. However, you will hit the pause button on further wear and tear and given the only other option is to re-install new pavers...its definitely the cheaper solution.