Thank you @TravellerG for sharing the insights.
Yes, group meetups are more common and have their benefits.
But the present post about solo meetups is to encourage people to go ahead with a meetup when there are not many local guides in a small place they might be living.
Sometimes, they host a meetup but no one turns up on the day.
So the meetup automatically becomes a solo. Not to feel discouraged and continue with the objective of the meetup.
There have been many such instances.
Here is one:
Recap - Brewery Opening Kraków
and one more:
RECAP - Maps Editing Walk in Kapasia