I want to say, you are not alone in your experience. Millions of people are dealing with social withdrawal. Alot of ppl misunderstands and assumes it's a choice when its often not. There are numerous reasons be they - environmental, Social, and personally that leads people to that situation. This phenomena is global and the numbers of ppl across the world socially withdrawing is startling. The rates of social dislocation, loneliness and disconnection are at sky-high rates as well. So this is a global social crisis that is happening.

I'm not going to give cliche solutions but I think checking out Dr. K's videos from HealthyGammer gives alot of insights on Psychology and mental health for today's digital age, so check them out, could be insightful. He made a video on this topic called 25 year old loner

This is a major problem that isn't being addressed. So many ppl are suffering and this issue isn't enough respect it deserves. To help people socially withdrawing the answer to the problem isn't just getting out there as you said, but adressing other underlying mental health problems.

Edit: Grammar, spelling