It’s not the ultimate barometer of course. But it’s telling he’s never won a thing!
Furthermore, you should probably have a look at Martial’s trophy cabinet - it’s not what we would want, but a hell of a lot better than Lukaku!
As a three, Rashford, Greenwood and Rashford outscored Liverpool. One was an 18 year old, the other two missed big chunks of the season. We are dramatically better without Lukaku.
Compare his 2nd season to Martials first season playing as our striker and he outperformed Lukaku in every respect. The PL is a far harder league than Italy - so that comparison is loaded.