[freehorse]

I don't know why USB dongles are popular for manufacturers (I assume to make their product more plug-and-play friendly), but I don't think they are a better solution than bluetooth. For example, it is common that if another USB device is plugged close to a USB dongle, it can cause interference to it, which results to unstable connection and eg makes a mouse "jump", keystrokes not register etc. Finding the right place for a USB dongle can be a pain. USB dongles with proprietary RF protocols are usually a terrible solution imo. I have never had any similar kind of connectivity issues with a bluetooth mouse or keyboard.

[bramhaag]

Some things are difficult to do with a Bluetooth keyboard: you cannot do anything before the OS is booted, such as changing BIOS settings, installing an OS, or choosing a GRUB boot entry. There are workarounds (buying a Bluetooth adapter that can act as a HID proxy) but for me this is enough of a reason to not want to rely on Bluetooth.

[notfed]

Bluetooth's latency is just too slow for a mouse. Heck, Bluetooth is too slow for audio, too, but most people seem to be complacent to latency.

[kergonath]

It’s fine for any use of a keyboard or mouse besides a niche in gaming. It also uses less energy than most RF dongles, which results in better battery life (something I could check using a couple of mice that could do both).

The fact that Logitech’s current dongles are just BLE with a fancy encryption scheme tends to indicate that they really want their proprietary hardware, and bandwidth is not the reason.

[brudgers]

The dongles are common because they predate widespread availability of bluetooth equipped laptops and desktops by about a decade…00’s versus 10’s.

Dongles are also plug and play (no pairing dance) and more readily support multiple devices on the same computer.

Bluetooth has gotten better over the years but it doesn’t provide a meaningfully better alternative for the it-aint-broke consumer mouse market.

[frollogaston]

I bought a new mouse recently and intentionally got a dongle one, not that it was hard to find. It's just better.

[m000]

USB dongles are popular because the mouse is paired with the dongle. This comes handy in a number of use-cases (servicing a different computer, hot-desk office, non tech-inclined people).

It is true though that USB interference for wireless dongles is an annoying reality. My Logitech Unifying dongle has issues whenever I copy files over USB. I'm not sure if later revisions or their Bolt dongles have improved on that.