The counter-argument to the obvious 'where are the goals coming from?' question is that we've seen the same attack, plus Lukaku, minus James, play superb football, score a lot of goals and win an extended string of matches (in fact, producing two months of mathematically league-leading form). Lukaku was rarely a starter and scored fewer goals than Rashford or Pogba and fewer goals+assists than Rashford, Pogba, Martial, and Lingard. He was not integral or even particularly influential during that successful period.
Then, of course, after the heroic victory over PSG by our kindergarten side on 6th March, it all went to shit. The injury crisis killed our momentum and from there it was a downward spiral of confidence and form. Notably Lukaku didn't score a single goal for us in this spell - he can no more be relied upon for goals when the team is struggling than anyone else.
You have to lead with the assumption that we're going to get something closer to the former period of form than the latter. If we go out and play like we did in the tail end of the season, we could be starting Messi and Ronaldo and we'd still lose every game, so all this is moot.
If, however, we come out with some confidence and belief in Solskjaer's system - which should be boosted by a much healthier looking defence, an actual RB and RW, and a crop of youngsters who have gone from 'talents for the future' to banging on the door - I see no reason why we shouldn't expect the
attacking unit to score goals, even if we don't currently consider any of the individuals to be suitably predatory. The evidence is right there is that first half of Solskjaer's tenure thus far.
For reference, our PL fortunes under Ole. Couldn't find such a neat table of our results in all competitions so you get this. Astoundingly clear 'two halves' here:
Of course, there's no way to know whether we'll see the United of January and February or the United of March and April. But the point is that the latter has very little to do with such niceties as the goalscoring instincts of our forwards. It was down to a total and utter collapse of form that renders all this discussion basically academic.
