That is a good option that has a large adoption among developers. For a big enterprise GSuite is great. Microsoft 365 is excellent for collaborative work as well. There isn't anything inherently wrong with services like GSuite or Microsoft 365. It's all about choice!
For smaller businesses, from my personal experience, Zoho is a great option. I like their stance on privacy while still offering great collaborative online tools and cloud management. Zoho is surprisingly well represented amongst integration services like IFTTT and Zapier as well.
Protonmail is solely focused on email routing and as an open-source activist and political organizer I feel much more secure with a company based in Switzerland that does not have the ability to read the emails I am sending regarding my activist email account. Since most of the individuals I consult with work in the political sphere that is why Protonmail is usually at the top of my list to suggest.
On a personal note I just installed Nextcloud 20 on a Raspberry Pi 4 (4Gb) using Docker and I have to say.. it's running great. I am using the ARM64 architecture. It was very, very difficult at first (mostly because I had to understand every minute detail) but the experience and final product have made me extremely happy.
All of my Contacts, Calendars, Tasks, and Notes are routed through Nextcloud. I still use an Android phone but I was happy to support independent developers and grab the DAVx3 and OneCalendar apps for use on my phone. There is full Dropbox-style cloud storage functionality and if something unexpected were to happen the device is right on my desk and it would be easy to just reach over and hit the power button. Nextcloud does have a Mail app that allows importing IMAP accounts if you wanted to use a work email that way.