So yes! You can do that - there’s a specific trigger in IFTTT called “When a Cell in Google Sheets is Updated” (or soemthing very similar)
I set up something very similar to do what you’re describing for American Express - I did a mini write up here
What I did was use Zapier to extract the balance amount from the regular email I got - apparently there are ways you can extract from SMS or Notifications in Android, but not iOS, so that’s the solution I went with.
The solutions’ a touch Janky because the IFTTT “Cell Update” doesn’t always fire on time reliably, but when it works, it works great.
The “Cell Update” idea is a great use case for the Google Sheets integrations, cos you can do so many more powerful things than Regular IFTTT alone can acheive. Things like “If my Balance is below X then Move Y from Pot”, or “If I spend more than £30 at McDonalds in 1 week then [other things]”.
Happy to help if you need it - this is my all time favourite Plus feature so if I can get more people using it I’m happy 