Tyrese Maxey #0 of the Philadelphia 76ers looks on during the game against the Boston Celtics. NBAE via Getty Images The NBA’s parity era has produced a different champion for the past seven seasons and we’re seeing the depth of talent across the league displayed nightly during the first round of these NBA playoffs. This year was the first time we had five first-round series tied 1-1 since the league adopted its current format in 1984, according to the NBA . Most of the series so far have been impressively competitive on the floor compared to the expectations on paper and the Celtics vs. 76ers series is a great example. The Celtics opened as -900 favorites to win the series at BetMGM , were -1200 before Game 1 and the most-bet team to sweep their opponent, then moved to -2500 after a blowout win in the opener. Entering Game 4, up 2-1 in the series, the Celtics are 7.5-point favorites on the road after a 108-100 win punctuated by Jayson Tatum’s dagger 3-pointer in the final minute. Celtics vs.…