So, i decided to do a 10 minute study. by comparing champions League semi-final goal tallies with championship playoff tallies since 1999.
Football league playoffs don't have the away goals rule and haven't since 1999.
I chose only the CL semis for two reasons, 1) laziness, and 2) more accurate data since there is a higher likelihood that there will be large scorelines in the earlier knockout rounds but where the away goals rule had a lower impact on match strategy.
I also included all extra time goals, from both sets of data, again because laziness but also it made sense since having the away goals rule reduces the likelihood of extra time occurring, and if this is about having more attacking football, which is a fan service, then having a higher chance of extra time as a benefit of not having the away goals rule gives fans more football for their money. Another byproduct of having more extra time is penalty shootouts become much more likely. Which is even more excitement. I didn't include those goals.
Anyway. Here are the total number of goals scored each season in the respective semis, and the goals per game at the bottom.
