Disagree entirely. An upgrade on Barry would have scored, generously, 2 more goals in the league (he has 1 goal from an xG of 2.7). Assuming that sort of rate of difference will continue is simply not really how it works, so you can't assume an investment would return that many more goals in the second half of the season - he's also been doing all the other bits of being a striker pretty well, so you also have to find a striker who presses just as much, wins as much in the air etc etc otherwise the opportunity cost goes up.
On the other hand, we have been playing like a lower-midtable team in terms of our overall performances, and again over the course of the season the reality of that will likely catch up to our actual table position. Fullbacks have a bigger impact on overall team play - they get almost exactly twice as many touches of the ball as our strikers *every game* AND there's the two compounding factors of a) our wingers are our most potent asset on the field and they're being limited like no other wingers in the league are due to lack of support or even anyone to pass to and receive from and b) it would cost us 20-30m max to upgrade RB to immediate top-half quality compared to about 70m at striker.
Sorry that was a bit of a waffle haha