So, this was a very brief search, with a niche site source, and not "average" games.
WNBA Finals viewership at four-year high despite quiet finish:

The four-game Sky-Mercury WNBA Finals averaged 548,000 viewers across ABC, ESPN and ESPN2, marking the largest audience for the event since the five-game Lynx-Sparks series in 2017 (559K).

LLWS dominates baseball viewing, but final is no match for 2019:

Sunday’s Taylor (Mich.)-Hamilton (Ohio) Little League World Series championship game averaged a 1.6 rating and 2.78 million viewers on ABC, down from both equivalent games in 2019 — the World Championship (River Ridge, La.-Curacao: 1.9, 3.02M) and U.S. Championship (River Ridge-Wailuku, Hi.: 1.9, 2.93M). There was no World Championship this year as international teams were barred from competition.