"Wasteful finishing" is one of those universal complaints that every single teams' fans complain about. Many times, it's us overrating just how high some scoring chances were (thinking they were easier than they actually are) while also underrating some of the goals scored from low percentage chances.
Coming into this game, our xG in Serie A was 58.58. Our total goals scored was 63. You can't really be accused of "wasteful finishing" when you're overperforming your xG (although obviously those numbers are in the same ballpark). Even last year, for the complaints that existed...xG was 71.97 for the season, we scored 71 goals, it was about as close as you can reasonably get.
Now, for the CL it is a bit different...our xG there is 14.6 goals, and we've scored 9. Specifically, 2.3 xG against Atleti vs. 1 actual goal we scored in the first leg. I'm blending sources here a bit (the website I use for league stats doesn't seem to have xG CL stats readily available), but if we're about +4.5 in league and -5.6 in CL play...again, it comes out pretty much as close as you can get. What ends up "hurting" is when you overperform the xG in games like @Salernitana (2.3 xG to 4 goals scored) that were easy wins regardless and then underachieve them in the UCL knockouts, but it is what it is.