Demaryius Thomas has departed, but only kind of. He returns Sunday as an instant reminder of all the Broncos have lost since Peyton Manning’s departure.

What a weird moment it will be to see Thomas trotting out of the east tunnel at Mile High on Sunday, wearing the colors of a Houston Texan.

He’s one of the most beloved actors in the Peyton Manning Era, in some ways the best era in Bronco history. Seeing Thomas on Sunday will remind us of the glories of the PM Era.

And remind us it’s time to embark on a new era. Boldness lifted the Broncos once. And maybe boldness can lift the Broncos again.

When Manning signed with the Broncos in March 2012, the franchise had won 28 games in four seasons and one playoff game since 2005. At the time, Manning was as a monumental risk. His neck was a mess, and his right arm, the most accurate in NFL history, was a mystery.

He transformed a franchise. In four-season PM Era, the Broncos won 55 games, including playoff victories, nearly doubling the total of the previous four seasons. No other version of the Broncos won as many games in four seasons. (The 1995-1998 Broncos won 54 games, including two Super Bowl triumphs.)

Playing alongside Manning earned Demaryius a massive stack of cash. After catching 226 passes in the 2014-2015 seasons, Thomas negotiated $35 million in guaranteed money, with an $11 million bonus. Only 27, the best days of his career seemed ahead.

He’s been solid since Manning retired, but seldom earthshaking. I hated to see Demaryius depart. I can still see him running in open spaces against the Steelers in the 2011 playoffs, on his way to an 80-yard touchdown as Mile High quaked.

The Tim Tebow-to-Thomas-TD ranks among the finest moments in Broncos history.

But it was time to say goodbye. No way would the Broncos pay Thomas $14 million next season. They were fortunate to get a fourth-round pick in return.

Thomas is not alone in receiving lush benefits from the PM Era.

After the 2012 season, Broncos offensive coordinator Mike McCoy was judged a rising NFL genius. Five teams — Bears, Cardinals, Bills, Eagles and Chargers — courted him as head coach.

McCoy signed with the Chargers, struggled to a 27-37 record and was fired. He’s been fired twice as offensive coordinator, by the Broncos and Cardinals, in the past 11 1/2 months. Without Manning running his offensive show, McCoy has never been described as a genius.

And then we arrive at the prime benefactor of the PM Era.

Yes, we’re talking about King John Elway.

On Feb. 7, 2016, I was standing in a joyous Bronco locker room. Cam Newton and the Carolina Panthers had just been vanquished, and the Broncos ruled the NFL for the first time since Elway led the franchise to supremacy in 1998.

Elway stood in the center of the party. He was, at that moment, the rarest of creatures, a superstar athlete on his way to becoming a superstar executive. He seemed ready to become the Jerry West of the NFL.

Manning was old, destined to retire in a few weeks, but the Broncos were young and hungry. The defense, under the direction of Wade Phillips, would remain magnificent in the 2016 season.

Anything, and everything, seemed possible for Elway and his Broncos.

Since then, Elway and the Broncos have lost 23 of 40 games, including losses in 15 of their last 20. Elway, a restless type, has shown aggression, but almost always aggression of the reckless kind. He banished Phillips, a franchise-shaking mistake. He hired Vance Joseph, a coach of unknown powers, and Joseph’s powers remain unseen.

When he traded Thomas on Tuesday, Elway revealed to everyone where his eyes are resting. He’s looking to the future, searching the horizon for another transcendent personality, another Peyton, to rescue a broken franchise.

Good luck on that one, John.