For FiveThirtyEight, Geoffrey Skelley digs into the ongoing trend:
What’s behind these increasingly older Congresses? The country’s aging population as a whole is chiefly responsible, which is most apparent in the disproportionate influence the baby boomer generation has on Capitol Hill. Coupled with longer-running trends that have made it more likely for members of Congress to win reelection and stick around, this has all helped make Congress older than ever before. And the overrepresentation of boomers doesn’t just produce moments like those of the TikTok hearings — it also has real effects on the type of policies passed by the federal legislature.