It’s actually surprisingly easy to do on a OnePlus 5T. I did it after cleaning out the port wasn’t good enough anymore (my phone was bought secondhand/refurb, and I also recently replaced the battery too . - overall the cost of both endeavours including the cheapo kit to get the thing open in the first place was on the order of £25, though I did lose the two screws for the USB port that connext it to the bottom, still works fine with the other two internal screws though 🤣).
Eventually secondhand parts will stop being available on ebay, but for now its all good ;p. Though if your screen breaks it’s probably not worth it to replace, that part alone seems to be half the secondhand-price of a lot of phones all on it’s own >.<
It’s a convenient file transfer/sync tool. Copying data has to happen somehow, I’m not surprised someone thought to use syncthing for that purpose >.<, since it can do that. But its not really different than any other tool here.