Yep, dating apps didn't work great for me at all because I have the misfortune of being both unattractive and picky, but couch surfing hangouts work fantastically, especially for meeting local people. Walking around at least puts you in places where people can talk to you, occasionally they do. Wearing unique or attention grabbing things gives people an excuse to talk to you. I always choose trains and buses to travel, conversations are more common there. Hostels are a very easy way meet other travelers and get your social fix when you need it. Often times the staff are friendly enough and if you stay in one hostel long enough or visit with them, the staff might integrate you into their social life. Most hostel staff like to travel, too. Becoming a regular at any kind of place will almost certainly get you conversations with staff. A lot of people you meet in hostels are traveling from the same country or ones you are going to visit, so you meet those people there.
At least in Europe (can't speak from personal experience elsewhere) you can easily find "Language Exchange" type meetups. Depending on the city, it will be a healthy mix of locals, immigrants, and tourists. If you speak English fluently, you'll typically have a lot of locals eager to talk with you to practice their English, and in turn you can learn/practice the local language in an open environment.
This is lower stress than trying to go to a random bar and strike up a conversation when I don't know the local language very well, and if you're staying long-term, it's a natural way to develop friendships with locals.
How do you avoid getting mugged or murdered from people you couch surf with? Basically avoiding the scammers...? I feel like in Europe, there are so many street scams and that if police aren't even willing to curb that issue, what recourse would you have if someone were to harm you while couch surfing at some random place? The risk feels pretty high to me. I guess you would have to travel really light in these situations?
It's actually very hard to get murdered in Europe if you're actively trying to avoid it. Same for getting scammed. The overwhelming majority of people are decent. The ones who aren't make the news because their behaviour is so unusual.
I highly recommend you give international travel a try!
As someone with mild social anxiety, the thought of doing something like that is utterly alien, even in my own country let alone somewhere else. I don't mean in a "i wouldn't do that" sort of way, but in an "i cannot even imagine/does not compute" sort of way.
I also have/had mild social anxiety. When things open up go stay for a couple days in a hostel somewhere (use hostelworld), make sure to find one with a reasonably large common room and be in it, read a book or do some work. It will probably be therapeutic. Not much is forced and socialness tends to just happen. If someone sits near you or says hi ask "Where are you from? How long are you here? What have you done here?" and roll with it. If you do some research on whats in the area or cool food you want to try, you have an immediate opportunity to invite someone to do an activity. It will feel like sitting on an airplane with the door open to go sky diving to you, exhilirating if you manage to make yourself do it.
A useful psychological hack: you have a bit of a desire to do this, hell, it's scary, right? So invite a friend and make it your goal to plan lots of things - its easier to do do something for others quite a lot of the time.
Be explict you are doing this. You'll probably find there are some great bits, some other bits you cant control that are exhausting, etc.
Then do another trip. Plan to invite that friend. Plan for the good bits and to avoid the worst bits. Then just go by yourself!
The first run through gives you a motivation to do something challenging and consider what you would think people want to do, even if its awks.
The second, you take the learnings and reward yourself
I have mild social anxiety. Maybe more than mild. I have to say sometimes it is easier to be social in another setting. For example, in hostels the expectation is to just start talking for no reason and tell that lone traveler that you are indeed exploring the city and inviting them to join you.
Another thing I've found is taking a class - in my case kickboxing classes led to quite a few new friends.
I don't have as much courage to do that in my home country.
How did you go about meeting people in the first place?