That's an argument within an argument within an argument. You've successfully argued against your own sub-argument but it doesn't get close to answering the broader point. Let's go with your Welbeck example. Is he a good goalscorer? No. Do goal stats tell you that? Yes.
Does the understanding of how he plays and where he plays extend your understanding of his goalscoring record, and his all-round output? Of course. But on the face of it, he's a 1 in 4 goalscorer. That's held true throughout his club career. Worse than someone like Louis Saha, and comparable to someone like Emile Heskey (in his 20s). Does it tell you anything more than that? Not really. But the goals records make those basic comparisons much more easier to do. It's one data point amongst many, but the consensus for decades is that it's a particularly important one.
It's the only information we have that takes into account every game and is correlated to overall effectiveness as a striker. The alternative is making assessments based on snapshots of their career, and for many people that is limited to just highlight reels. That's full of rich information but also full of gaps. The data quality issues are obvious - high validity, (often) low reliability. Goals are the opposite of that: they're much more reliable as they aren't just selective samples, but full representations of their career, but on the flipside they only tell you so much.
No-think thinks stats tell you everything, so your strawman argument exists for one purpose only - you have a strong opinion that morphed into an agenda after having too many discussions on here about stats. We all agree that stats are flawed. Goals are the most useful, by a distance, but they're still flawed. If you can only see the flaws and can't see the value, fair enough. But your explanation of it doesn't fit the evidence. There is a strong correlation between forwards' goal totals and their valuations, and that has been there for as long as valuations have been meaningful. You can argue that everyone else is wrong, but you can't explain it away by saying it's the managers trying to explain this complicated game to the common folk. They use it themselves, indirectly and sometimes directly.
The nuance here is I'm not saying that managers pay the most money for the best goalscorers - it's just a correlation, and other factors come into play. However to deny that goals are in any way in important in assessing strikers is an opinion so far outside the norm that it would need some evidence to support it. The available evidence suggests the opposite.
