daredevil Possession football is a predictor of creative and attacking football. The teams who play the most creative and attacking football generally record the highest average possession. Obviously, you can be a boring or relatively conservative possession team.
I'd say possession is an indicator but not a definitive predictor. Last season if I recall correctly we had less possession on average than we do this season with the consensus being we were more exciting to watch (particularly 1st half of the season). And whilst it was a different era, I recall the Invincibles often had relatively low possession despite their seeming relentless creativity (we were just more ruthless on the ball rather than requiring oodles of possession).
daredevil I think where we differ is I don't agree that England's talent pool possesses so much creative talent that we should lean into it because it would materially improve results.
Gareth, is that you? 😉
This probably is the main point of divergence.
You've said that we wouldn't win against the big teams if we played more offensively - by and large, we don't win against the big teams with our current approach!
As you referenced Venables, I think he's a good example of someone who did take a more attacking approach, to great effect in Euro 96. We had some decent (but not world class) set of attacking talent yet played a somewhat dysfunctional but still primo Dutch side off the park.
So in summary, if you find an attacking system that works (which I think is not measurably harder than constructing an efficient defensive unit), then you can reap the rewards.
Finally, I think your wider point about international managers defaulting to being defensive is less about the challenge of playing offensively and more about the general dynamics of international football. For a big nation, you're judged on your performance in tournaments that occur only once every two years - therefore conventional wisdom encourages conservative play as it's seen as less risky when the prize is so great and therefore less likely to get you sacked. But I'd still see that as a failing of a second rate manager who isn't able to achieve anything beyond a basic level of defensive competence.