I have a web-hosted NextCloud instance set up as my syncing target, for keeping track of approx 800 notes on multiple devices, and it works flawlessly most of the time!
I recommend you'd purchase an upgradable Nextcloud web-hosted instance at a provider for really cheap to get started. It's easy to install and easy to use for testing the waters before fullly diving into self-hosting. Make sure to make an informed decision before buying!
For me who had zero knowledge about server adminnistration and self-hosting, but wanted to move away from OneDrive and Dropbox (as far as possible!), it took only a few hours of learning and fiddling around to set it up! Some providers, such as Cloudamo for my part, include a ready-to-install Nextcloud script so you don't have to install Nextcloud manually from scratch.
I wouldn't recommend signing up for a free server, unless you want to test and play around with Nextcloud first, because you may have no access to your server's settings and minimal support if something goes wrong.
Here is one way to get space (1GB), support (by email) and a reasonable speed, all for free: nextcloud on cloud.woelkli.ch in Switzerland.
It has worked fine for me ever I set it up with Joplin desktop, no glitches since summer last year. And if you are willing to make a small annual donation (way under par than their paid plans) these people will even be happier.
I use Joplin with Syncthing which works great. Syncthing enables you to sync your Joplin folder on each device with each other. You can install Syncthing on for example your phone and laptop, but they both need to be turned on at the same time to sync. What I do is have another Syncthing installation that is always on, on a Linux server, but you can use a Windows desktop or even an android tablet as well.
I really like the fact that my sync is decentralized. So, when my Linux server goes down because I am a selfhosting amateur or because the internet infrastructure is down, my sync process still continues via my other vps or even without internet via LAN.
I started with OneDrive (yes, issues with larger files) as I pay monthly for O365, then I moved to Dropbox and it was working fine. Then I tried NextCloud at external provider and it was a disaster speed-wide. Initial sync took several hours (few times longer than Dropbox), so I went back to OneDrive, also scrapping all database and restoring JEX backup. Dropbox works best for me. I didn't migrate fully from EN (I still use it for garbage dumps) but my new text notes are in Joplin.
as I said above, syncing with free servers was slow, so at one point I decided to setup a RaspberryPi server (NextCloudPi) at home. was easier than I expected. even a full sync is pretty fast since everything syncs via the local network. incremental syncs are fine even when connecting externally (although slower) from outside the house (doesn't happen very often lately...). I'm curious to see how the new Joplin Server will perform on the RPi.
Topic starter suggested he is not very confident at running his own server via commandline I think. Else a Raspberry PI server at home would be great. Or perhaps an old laptop, maybe you can even run a Docker Nextcloud instance on Docker for Windows (or Syncthing which I am quite fond of ;)? In that case its quite easy for a non-specialist to configure the laptop to not turn off.
Talking about free hosted options, you also get much more speed when you self-host. The big 4 cloud providers all offer some free tiers. Be aware of their accumulated bandwidth limits though. This is actually how I learned to self-host a Linux server. On the Oracle cloud VPS you can run a single instance with 100GB free space, or two separate instances with 50GB each. I remember the Google Cloud Platform to have quite restrictive in terms of bandwidth. Amazon AWS is great, but the free-tier stops after a year. Never got to experiment with the Microsoft Azure one.
Since I trust my personal sysadmin skills much less than Dropbox or Onedrive w.r.t. uptime, I was less confident with the availability of a personal Nextcloud or Seafile instance. With the decentralized nature of Syncthing, I do not necessarily need the cloud server inbetween, however, one or two cloud Syncthing servers make it more reliable and remove the need to have both devices with Joplin on at the same time to sync.