Hmm, the long timeframe makes me wary of the comparison. The problem is, the comparison holds weaker and weaker over shorter timeframes:

https://meta.wikimedia.org/wiki/Wikimedia_Foundation_Annual_... Planned spending 2019 ~92mil

https://stats.wikimedia.org/v2/#/all-projects/contributing/e... - ~130% page edits growth 2012-2019 (~35mil expenses, a 260% increase)

https://stats.wikimedia.org/v2/#/all-projects/contributing/e... - ~80% page edits growth 2015-2019 (~65mil expenses, a 140% increase)

The rate of increased page edits is closer and closer to the rate of increased expenses. I personally don't think that's a convincing argument, because I haven't seen this massive improvement in tools to justify the extra costs(most of the extra expenditure doesn't seem to be on development, anyway), but I don't think the argument can be dismissed out of hand.