Dressel won eight medals, including six golds, at the world swimming championships, the biggest meet outside the Olympics. Two years ago in Hungary, he tied Phelps' record of seven golds at a single worlds, including three in one night.
Dressel set his own standard in Gwangju, where he again won three golds in a single night.
"There's parts during the meet where it's not the greatest feeling — the stress that you feel, the pressure I put on myself," he said, adding, "I do enjoy it, the challenge that it brings."
On Sunday, Dressel capped his eight-day run with silver in the 4x100-meter medley relay. He hauled the U.S. from fourth to first on his butterfly leg with a split of 49.28 seconds — the only sub-50 second fly leg in the field.
Had anchor Nathan Adrian not been overtaken by Britain's Duncan Scott in the closing meters, Dressel would have won a seventh gold. Adrian and relay teammates Ryan Murphy and Andrew Wilson were upset they didn't deliver.
"I was the first guy in the water and I would say I had a pretty embarrassing performance," Murphy said. "It kind of put us in a hole from the beginning."
Wilson added, "All of us are just finding places where it's on us. We just all need to be better and we will be next year. It's frustrating now but it's fuel for the next year."
Heading into its first Olympics in the post-Phelps era, the U.S. appears in good shape for Tokyo.
After a slow start in Gwangju, the Americans finished with 27 medals in the pool, including a leading 14 golds. They won the team title and Dressel earned male swimmer of the meet honors. The U.S. set five world records, including two by 17-year-old backstroker Regan Smith.
Australia was second with 19 and five golds.
The U.S. likely would have had two more medals if Katie Ledecky hadn't gotten sick. She withdrew from the 200 free heats and 1,500 free final while spending two days away from the pool. Her lone gold came in the 800 free after a gutsy last lap in which she pulled away from Italy's Simona Quadarella.
The Americans were limited to one medal on two different nights — both earned with Dressel's involvement.
"It's pretty evident that we didn't start on the best note," said sprinter Simone Manuel, who swept the 50-100 freestyles, "but also we did have a great meet, and I think that's getting a little lost because we had amazing swims, people got best times."
Dressel's golds came in the 50 and 100 free, 50 and 100 butterfly, mixed 4x100 free relay and 4x100 free relay. His other silver was in the mixed 4x100 medley relay.
Dressel took down Phelps' world record in the 100 fly, going 49.50 in the semifinals.
He came close in Hungary, but didn't get it done.
"Two years ago I was a little scared, I'll admit, coming that close," Dressel said. "It can be a scary thought to do something that's never been done before."
The difference in Gwangju was that Dressel woke up the day of the race and wanted to go after the mark.
"I hope he was happy watching me," he said.
Dressel still feels his retired teammate's influence. He knows the 23-time Olympic gold medalist's times and watched how Phelps swam his races.
"It's really special for me just to have that one little moment where I claimed I was the best in the history of swimming," Dressel said. "Just a young kid from a small town, it's just crazy how far the sport can go."
Like Phelps, Dressel is his own worst critic. The 22-year-old Floridian picks apart each of his races, whether the result is gold, a world record or something less lofty.
"I always look for the bad," he said. "There's plenty to improve on. I know what to look for heading into next year, even for small meets. I take each event and I have to learn from it."
What he learned in Gwangju is that he's his own man.