I really like Wild Bill, most Brewers fans do. The problem is he's a catcher. I don't value catchers past age 30. More importantly, I think the Brewers have shown they do not either.
I was prepared to come into this comment saying "If Contreras aged like Yadi Molina, then I'd take it." Because my perception was that Molina actually improved offensively in his 30s.
Then I went to FanGraphs and was proven (mostly) wrong.
Yadi Molina (age): wRC+/WAR
2012 (29): 138/7.5
2013 (30): 133/7.2
2014 (31): 102/3.2
2015 (32): 81/2.4
2016 (33): 114/4.5
2017 (34): 95/2.5
2018 (35): 105/2.7
2019 (36): 88/1.9
2020 (37): 83/0.7
2021 (38): 81/1.5
2022 (39): 49/0.2
2023 out of baseball
He still produced 2.5 to 4.5 WAR through age 35 even as his wRC+ sank to more average levels but he was also one of the best defensive catchers in MLB history. He was getting WAR in the 4.5 to 7 range in the half decade prior to age 31. All in all though, he gave the Cardinals mostly productive seasons late into his 30s.
I just don't think many here would be loving 80 wRC+ offense from Contreras judging how they are reacting to it this season. So let's take a look at him.
William Contreras (age): wRC+/fWAR
2022 (24): 139/2.0 - his last season with ATL
2023 (25): 126/5.8
2024 (26): 132/5.5
2025 (27): 113/3.6
2026 (28): 107/1.6 (so far)
Doesn't look like it's trending the right way to me. He's trending to be about a 3ish WAR player this season, maybe he can reach 4 WAR. He had 3.6 WAR last season and is already down from his peak seasons.
I don't know what an extension would look like, maybe he would agree to a number the Brewers would find reasonable. I wouldn't want to sign him past his age 33 season though. That would be a 4 year extension. So maybe? I get the feeling though that he probably could get more on the open market than the Brewers would like to pay and maybe more years too.
Just for giggles I also looked up the last two star catchers the Brewers had before Contreras.
Jonathan Lucroy (age): wRC+/fWAR
2016 (30): 123/4.4 - Last season with MIL (traded to TEX mid season)
2017 (31): 80/0.0
2018 (32): 72/0.3
2019 (33): 74/-0.3
2020 & 2021 he played 8 games total and was out of baseball
Yasmani Grandal (age): wRC+/fWAR
2019 (30): 121/5.7 - Only season with MIL
2020 (31): 114/1.6 - Signed FA deal with CHW at 4 years $73M
2021 (32): 157/3.6
2022 (33): 68/-0.5
2023 (34): 80/0.0
2024 (35): 95/1.3 - .700 OPS, 9 HR, 26 R, 27 RBI in 72 games for PIT
2025 out of baseball after a brief minor league stay with BOS
I feel like these two guys are more realistic. Lucroy had the bad luck of declining just before he hit FA and never signed a big contract but Grandal cashed in and had two decent seasons before decline after his age 32 season.