My Internet goes down at least twice a year and my electricity goes down even more, specially in the winter. So no, this is not more reliable than cloudflare.
In a discussion about using a CDN, it's implicit that it represents an addition to "professional" hosting with servers in a well managed data center that has, at least, redundant high-bandwidth network connections, not to a domestic network connection.
Note that your home network could be good enough for a personal web site that nobody pays you to respect a SLA on.
No, we're talking about a colocation provider, or a leased dedicated server provider. I went with OVHcloud US for my latest deployment. HN is at m5hosting.com.
You seem to imply that the options are only cloudflare or your apartment. This simply isn't true: there are a plethora of companies that will lease you a dedicated box of some Us in one of their racks, as the sibling commenter replies. Alternatively, you can search for co-location services. Options range from 1U/2U co-location, to half rack units, to full racks, to dedicated areas of the datacentre ranging from cages to whole rooms (I've been in at least one datacentre where an entire room was under separate access control and leased to one customer only).
Usually datacentres are located quite strategically. For example the location of many datacentres in Zürich corresponds with two separate power supply grids that meet (so they can pull from both).
Some of the companies involved are resellers and don't actually operate the datacentres they use. Others actually do. Usually the service is more or less the same, from the point of view of renting a 1U, or co-locating one.
If you want reliability features of a datacentre, e.g. for your office services, but might move, you may find your local city surprising. In Manchester, UK, there's a large amount of dark fibre under the city (fibre that is laid, but not in use), owned by some of the DC companies. Sometimes you can connect your office to said datacentre via dedicated fibre.
My Internet goes down at least twice a year and my electricity goes down even more, specially in the winter. So no, this is not more reliable than cloudflare.