So, basically:

"I have spent most my entire life outdoors from dusk to dawn, and things have changed over the last 20 or so years with what we have been seeing in the sky."

I spend over a decade of my life working around airplanes—first as a refueller at the YYC and then in airline operations & training with a major Canadian airline. The reason things have changed is because things have CHANGED, and I mean radically so. I'm old enough to remember an entirely different airline industry.

You don't see the "same contrails" because you don't "see" the same planes. And back then the jet engines weren't as advanced as they are today. The skies back then were jam packed with jets like the 727, MD-8X, the 737-200, and the most common engine in the skies were the low-bypass turbofan engines such as the Pratt & Whitney JT8D (look up a pic of it!). These engines were dramatically less efficient and produced way more emissions compared to modern high-bypass turbofans. Low-bypass engines have a smaller ratio of air bypassing the core to air passing through the core, making them less efficient, the exhaust has significantly higher levels of unburnt hydrocarbons, carbon monoxide, and nitrogen oxides, and tons of small dusty particulates. Look up a 727 taking off. They look like a B-52! They mixed with whatever water vapour was in the exhaust and quickly fell to Earth. See how dirty they are??

THAT'S why they were different.

You are correct, you are noticing changes, but it's time to "notice WHAT you are noticing." Damn right things have changed since you were a kid, and here's what's changed:

• WE FLY SIX TIMES MORE MILES IN THE SKY THAN IN 2001. The cost PPPM (per passenger, per mile) has literally dropped like a stone, meaning that it's cheaper to fly now than at any other time in history.
• WE FLY ENTIRELY DIFFERENT ROUTES NOW THAN WE DID IN 2001. Back then, it was "hub and spoke," and it was common to make a stop (usually in Denver, Chicago, or Minneapolis) on your way across the country. Not anymore. Now pretty much everywhere you fly, you can pretty much get a direct route there. This means a few things:
• PLANES FLY LONGER ROUTES AND STAY AT HIGHER THAN EVER CRUISING ALTITUDES. It used to beg FL28 on average (28,000 feet), now it's FL33, and even altitudes on up to 38,000 feet are common, now.
• ENGINES ARE MORE EFFICIENT. Look up the GE LEAP-1B, which powers the 737 Max AND the A320NEO). Compare the 737-MAX's super advanced LEAP-1B jet to the JT8D. It delivers 35,000 pounds of thrust vs the JT8D's 17,000 pounds of thrust ALL WHILE BURNING 20% LESS FUEL per flight hour. How does it do that?? Because it burns SO MUCH MORE efficiently. And the rest of the planes now are made of composites (the entire Max is mostly composite, including the wings, tail, and body tube). That saves weight, meaning the airlines can do more up there and offer more of everything.

THAT is what you are seeing over the past 20 years. Flying at FL250 (25,000 feet) generally results in fewer contrails compared to FL350 (35,000 feet) due to atmospheric conditions. At higher altitudes like FL350, the air is FAR colder and more humid, which are prime conditions for contrail formation when the moisture in the air condenses and freezes around aircraft engine exhaust particles. In contrast, at FL250, the air is typically warmer and less saturated with moisture, reducing the likelihood of contrail formation as the conditions are less conducive to the moisture in the exhaust freezing into ice crystals.

THAT is why you see more contrails.

But of course, It's not changes to the airplanes or the airlines or the way we fly or the fact that you can fly from New York to LA for 500 bucks these days. It's the CIA!