The 2021 team which had Burnes, Woodruff, Peralta, Houser and Lauer won 95 games.
The 2022 team had Peralta, Woodruff and Houser all miss time with injuries. In their place Jason Alexander, Chi Chi Gonzalez Ethan Small and Andy Ashby make 32 starts for the Brewers. Those four combined for a WHIP of 1.56, they allowed a total of 26 homers in 158 innings (1.48/9). Next, their bullpen just wasn't as good as it was in '21 and they had several relievers pitch a significant amount of innings and perform poorly: Taylor Rogers, Matt Bush, Trevor Kelley pitched a combined 69.2 innings allowing 61 hits, 30 walks (1.31 WHIP) and allowing an astronomical 21 homeruns (2.71/9).
Thus I don't think Matt Arnold's task in putting together the 2023 roster is complicated. They intend to rely on the same starting pitching from '21 to win games for them in '23 and are banking on having better health. That they jettisoned Suter, (66 IP) Boxberger (64 IP), Gott (45.2 IP), Gustave (28 IP), Perdomo (23.2 IP) along with Rogers leaving as a FA means the Brewers are making nearly wholesale changes to their bullpen and hoping for improvement there. Certainly, the Renfroe trade appears to fit that narrative as Junk, Pegeuro and Seminaris could all be competing for bullpen spots in '23. I would also assume the Brewers will be shoppers for free agent relievers once the closers have signed and set the market.
As someone else pointed out, they also appear to be moving away from the "all or nothing" type of hitters who rip 30 homeruns and struggle to reach an .800 OPS. Further, as would be expected of any team without a 200 million dollar payroll, their prospects and bonus babies who reached AAA (Mitchell, Frelick etc.) will be given a crack at making the major league team. I would also expect the Brewers to be bargain shopping for 3B, C and even 1B and are willing to wait out players like Drury, Justin Turner, Jorge Alfaro, Gary Sanchez, Brandon Belt, Evan Longoria, Wil Myers Edwin Rios etc.