This is a classic argument. There are pros and cons to both sides. Cons of SaaS are its a honeypot for hackers and privacy. Cons for local are you become the IT department. If your Mac fails or is stolen, you lose data unless stored/synced elsewhere.

Generally, HSI (Highly Sensitive Information) or proprietary data, local-first with E2EE is the gold standard. This is an area of debate for a lot of people.