Slow download speeds

[Konstant K]

I have been having slow download speeds for the last week, as in 700 kb/s, usually I get about 8-10 Mbps. I have cleared my download cache, changed download region, reinstalled steam but still have slow download speed.
I know this is not a ISP problem because I have downloaded some games from Riot Games to see their speeds and I am getting my usual 8-10 Mbps, I have also download different large files from my web browser and getting my usual speed. I have my network drivers up to date. I have also tried to "disable writing cache on device" but that didn't help and have re-enabled it.
So, I am unsure what to do about this. Any feedback would be greatly appreciated.

[Elucidator]

You don't magically reach Steam, your connection goes through a number of computers. This path is decided by your Internet Access Provider.
https://en.wikipedia.org/wiki/Routing
Sometimes by their partners (they may have Internet Access Providers themselves). They see an IP where you try to connect to, and then decide a route. Sometimes these routing servers are extremely busy for reason such as maintenance or simply the time of day.

For example, one such lag point is the common route that makes a connection cross from the UK to the US; the undersea fiber glass cable opened up for normal internet users.

On the other hand, using VPN services, such as WTFast who has their own routing tables, may actually increase speed and connection stability due to them using not a default route to reach a particular server.

Anyway, if the computers on your road map have issues, you also get connection issues.

This is why in such cases, people sometimes fix their issues with speed by picking a different download region. The route changes to a less occupied one, and boom, increased speed.

Sometimes changing DNS may help. A tool such as Cloudflare WARP may also fix the issue if it stays, but anyway it maybe fixed in a few days on its own.