I don't think we have a leadership vacuum.
We do have an athleticism/energy vacuum though, midfield especially, as that pressing monster hasn't been there for Jurgen's last two years.
He let (or was it the restrictions imposed upon him) the team get old and slow.
We needed an injection of legs after Paris, as that midfield was running on fumes (Hendo needed replacing there and then, his closing down numbers had been on a steady decline over two seasons, Fabinho we didn't know he was done). We did nothing that summer, bar a token Kabak-esque late loan for Melo, and with "all those leaders" (Hendo, Milner) we got overrun by teams all season. That press conference Jurgen did in the August in an attempt to allay concerns about the midfield came back to bite him. We have only marginally addressed this with mobile 8s being brought in but with Mac being asked to "do a job" in the 6 it's still a patched up job.
The one thing Jurgen needs for his intense, pressing style of play to work is athleticism and energy, something we now lack. We've been vulnerable and ropey in every game bar maybe five this season (I'm possibly being generous saying five). Conceding six in two games vs toothless United, a team that athletic teams put to the sword (as Crystal Palace did home and away), we are a flaky outfit with no defensive protection in midfield. Like last season it takes very little for the opposition to get through to our back four. Speaking of Palace, they were also unlucky not to do the double over us given how we got out of jail at their place with the soft sending off that changed that game in the last 15 minutes. We never looked like scoring, and their athletic side overpowered the midfield. First half at Anfield they again exploited the lack of athleticism in the 6, and only when Jurgen made the half time change of the 6 did our tempo increase and we then tried to recover it (for the 23rd time this season) but it wasn't to be.
Don't like to use the word overachieve because ultimately if you achieve something that means its within your grasp, however circa 80 points and a Cup is a great achievement for a team that is still a work in progress with one or two key signings short, an obvious one being a quality 6.