I use Google Sheets for all my finances, it's great.

I have an Expense Tracker UI within Google Sheets that allows me to submit expenses to the main sheet (currently just over 5000 rows of expenses over the last few years)

I only just recently vibe coded a web UI tool that uses a Google Service Account to add expenses to this Google Sheet for me, and then created a Progressive Web App from that so I could do everything on my phone.

In summary, Google Sheets is sometimes all you need instead of a database for very simple applications (and built for an audience of one)