I feel that convincing people to pay monthly/yearly for something that has minimal monthly recurring expenditure/investment from the provider (unlike utilities, streaming services, etc.) is one of the biggest cons of the modern era.

I have Office 2010 on an old computer. While it lacks some modern features of Microsoft 365 (for example, Office 2010 is much, much faster), it still works seamlessly with any files I create in 365. And I only had to pay, once, about the same amount that Microsoft is charging for a year's use of the same suite in the present day.

So they throw in a few gigs of OneDrive to supposedly justify the cost? That vendor lock-in is obviously part of the con (see for instance the complete and very deliberate lack of portability of documents created in OneNote, if you don't have the Professional/Enterprise version). And there are innumerable better services out there, many of which are even free.