1.
GoodTask. It takes Reminders to a whole new level. Adds things like start date, recurrence based on completion date, custom filters, Kanban boards and a lot more. And because it works on top of Reminders, you're not tied to a proprietary database.
2.
Maccy. It's a clipboard manager like the one built into Windows. (Shame that there's no built-in clipboard manager in MacOS).
3. Onedrive. It is superior to iCloud in many ways, mainly because of (a) file versioning for all files, which also works as ransomware revcovery tool since it keeps up to 500 versions (b) it's cross platform so you can also get it on Android and Linux (and Windows of course).
4.
Cryptomator. It's an encrypted file storage app.
It's cross platform (Mac, Windows, Linux, iOS, Android), and super stable (I've used it for about a decade now with not a single hiccup). Also optimized for use with mobile devices.
5.
Linear Mouse. Because the default mouse acceleration and scrolling in MacOS were designed by reptiloids.
6. MS Office. If you live in the US and your work has a MS Office subscription, you most likely qualify for Home Use program which comes to about $50/year and includes 1TB Onedrive space and all basic Office programs on all devices. I prefer Excel to Numbers, but also Office is far better for use in a cross-platform environment, and for long term document storage. There's a gazillion apps on all platforms that can work with Excel format, but none that I know of outside of Apple ecosystem that can open Numbers.
7.
Affinity Photo. It's reasonably priced, one-time purchase for the current major version, very good photo processing tools, good RAW tools, and it is also available for iPadOS and Windows.
8.
XNView MP. A freeware photo viewer with some organizing tools. If you keep your photos in places other than iCloud, it's the best free Photos replacement that I found (at least for viewing and classifying, editing is very basic).
9.
Bitwarden. Passwords would be great if they allowed to exclude FaceID unlock from specific records or groups of records. I do not feel comfortable having all of my financial accounts protected with just FaceID. Bitwarden is also cross platform so your password database is available on any device.
10. Windows App for remote connection to PCs running Windows. So when I am working from home and don't feel like sitting in the study (or don't need large external monitors) I can use my MBA and not the stupid Surface.