Nextcloud is feature-rich, but a little slower and vastly more complicated than a CalDAV server like Baikal.

OpenSMTPD. I run a private mail server for family, and it works flawlessly. No maintenance aside from backups and occasional OS upgrades. https://poolp.org/posts/2019-09-14/setting-up-a-mail-server-with-opensmtpd-dovecot-and-rspamd/

Don't use Outlook for non-Outlook email services. Problem solved. I am required to use Outlook for my work email, but I keep all of my personal email separate, accessed with FOSS email clients.

Care to elaborate on the significant downsides?

If Hugo stops working down the line, you can compile your markdown with something else. Simple is king!

My OpenBSD operating system on my laptop is set to randomize my MAC address at every boot.

OpenBSD

Doesn't work with Javascript blocked.

Not my experience at all. Once my OpenSMTPD mail server was set up 3 years ago, the only time I spend on it is updates (like 20 minutes per year). Setup did take some time, but it was totally worth it to me.

Laptop not a server, huh? I am writing this from a laptop running OpenBSD, which is my main work and play machine. Works great.

No.

personal

Decent used laptops are quite affordable. I recently scored one on Ebay for under $100. It runs Linux and everything is snappy.