MacBook charging extremely slowly, after using 3rd party USB-C charger
I doubt it's just a coincidence.  There's more to the Apple chargers than just &quot;give juice to the battery&quot;, but I couldn't tell you what another charger may have done to your system.
It could be as simple as an SMC reset (The SMC manages low-level settings such as battery management).
From howtogeek.com:

Unplug the power, then shut down your Mac.
Hold the left Shift+Control+Option keys down, then press and hold the power button down. Keep all four buttons pressed down for ten seconds, then let go.
Plug the power cable back in, then turn on your Mac.

Here's the official SMC reset page from apple:  T2,  Intel chip