Unfortunately, no. Google Maps does not support this.
You can only zoom the camera in to the map to make the labels look bigger.
Or you can use Mapbox. It supports text resizing.

I am using Online Maps with the Google Maps provider and find the labels for cities and countries to be quite small. Is there a way to increase the size of these labels to make them more readable?

Any help or suggestions would be greatly appreciated!

Thank you!