Yes it is still working fine for access to my cameras when I am not connected locally on my network. I use the OpenVPN app on my iPhone and then UI3
Blue Iris web interface. If I recall piVPN was easy to install. I created a cron job for Dynu to keep my IP address up to date. Instructions are on Dynu. All that said I don’t use it as much recently because I am using Home Assistant for a lot of home automation and have Blue Iris integrated with it. All of my cameras are available through the Home Assistant app. Not as good as the Blue Iris UI3, but good for quick glance and the I can always switch to UI3 to look at details on alerts etc
I don’t have any experience with Wireguard, but if it is easier I would certainly go that way.