You have to go back to a Hall of Famer who last played for the Blues 20+ seasons ago to find an example. Point proven?
What measure are you using for effort? Kyrou gives effort. He just gets zero slack from a vocal group on here. One mistake or "lazy" play (even one where he was on the end of a long shift) and he loses all the credit for multiple games worth of effort.
I went back 20+ years to illustrate a point.
We loved Chopper. We hated Housley.
There have been plenty others over the years.
We love Broberg.
We loved Petro.
Krug was winning a lot of us over until his body fell apart.
We loved Shattenkirk.
We loved Dennis Wideman.
Heck; we liked Colaiacovo.
There have been plenty of non-physical "offensive" defensemen that Blues fans have loved. The difference is that we can see the effort from those guy while we don't see it from a guy like Perunovich.
Another thing to consider is that Blues fans largely aren't stat watchers. Especially with regards to advanced stats. Effort is judged by the eye test for most of them; but when you're showing up as a -30 it's a little hard to overlook.
As for Kyrou; other than one troll who is mostly just being mocked, most of us freely acknowledge that Kyrou has come a long way in terms of his defensive play. His track record isn't great so it's going to take an extended run to wash himself completely clean of it(which hasn't happened yet), but he's absolutely made big strides and we acknowledge and respect that for the most part. Conversely; even on the same team, we love Bobby Tommy. And he's not even remotely a "physical" player either. What separates them is the visible difference in effort. We see Thomas trying to outwork people. We've only recently started seeing that from Kyrou and it's still inconsistent.
Blues fans relate to "hustle" and "effort". It's not about being physical.