Absolutely not. They have way more money than they can sensibly spend, keep begging for more as if they could barely keep the lights on (they could probably easily keep the core mission going with about 10% of the money they're getting), and then expand their spending to match the donations they collected.

They then created an endowment (i.e. a pile of wealth that generates enough interest to sustain them indefinitely), using both additional donations and some of the money given to Wikimedia (which reduces the apparent amount of money they spend and is not listed as money Wikipedia/Wikimedia has, as it is accounted for separately). The $100M endowment was planned to take 10 years to build, got completed in 2021, five years before schedule. Wikimedia also has a separate cash hoard of almost a quarter billion dollars.

It's actually all in their article: https://en.wikipedia.org/wiki/Wikimedia_Foundation#Finances