Russell may be a 2WAR guy even if he hits like Frank Castillo, I get that. I'm just saying that if he could hit a little bit, or even get up to or close to or even a shade above average, he'd have a LOT more market value than as a strictly defense-only guy. You can calculate value based on present market-value and past-performance. But his future performance, who can guess? Maybe he'll be in the 74-84 range again of last two years; maybe he'll rebound and get back into the 91-94 range of his first two years; maybe with some age and maturity and good health and good coaching he'll show the age-based improvement that many people anticipate back when he was 21 and he'll blossom into a 100-105 guys.
The defense is pretty predictable; it's going to be elite. >90th percentile in the whole game in terms of defensive value.
But the offense is very unpredictable. Might be <10th percentile; might improve into the 20th-40th percentile which would be a huge step up for any offense playing him every day; or might improve up into the 40th-70th percentile and be no liability whatsoever in the lineup. If you didn't have to sacrifice scoring to play him, his value will go way up, whichever WAR calculation you use.
I think there's something of a composite team factor for offense. Red Sox catchers as a group were even worse offensively than Russell last year, and their offense rocked nonetheless. So as Blue has often noted, *IF* the other guys rock, Russell can be an auto-out and we can still have an elite offense. But Red Sox had two >1K guys, and of course no pitcher batting. So an opposing pitcher still had to respect 8 guys, and it was only 1/9th of lineup that was an auto-out rally-killer.
I think it's harder to sustain a non-HR-based scoring inning when the number of auto-outs increases. Sure, if Schwarber and Bryant are posting 1.030 OPS seasons, everything's going to be fine, whether Russell is a 5th-percentile or 45th-percentile hitter. HR's are huge, of course; if the Cubs could be one of the stronger HR-hitting teams, you can score anytime. But if you're trying to score by bunching ≥2 hits in a given inning, that's hard enough when you've got three outs; it gets harder when you're giving away auto-outs. Hopefully Russell will be considerably upfield on the anti-awful spectrum when he's in the lineup this year.