[iaw]

Not entirely true: " The average age of Members of the House at the beginning of the 116th Congress was 57.6 years; of Senators, 62.9 years." [0]

[0] https://guides.loc.gov/116th-congress-book-list

[nprz]

And interestingly, that number has been steeply increasing since 1980 https://i.imgur.com/6eiPP3z.jpg

[paxys]

Older members of congress wield significantly more power though by way of seniority and committee memberships.

Joe Biden (President) - 78

Nancy Pelosi (Speaker of the House) - 81

Steny Hoyer (House Majority Leader) - 81

Jim Clyburn (House Majority Whip) - 80

Chuck Schumer (Senate Majority Leader) - 70

Mitch McConnell (Senate Minority Leader) - 79

Patrick Leahy (President pro tempore) - 81

Dick Durbin (Senate Majority Whip) - 76

Most committee chairs/ranking members are 70+

These are the people running the country. A 30 year old first term congresswoman has next to zero influence in matters like this one.