The main downside of docker images is app developers don’t tend to play a lot of attention to the images that they produce beyond shipping their app. While software installed via your distribution benefits from marriculous scrutiny of security teams making sure security issues are fixed in a timely fashion, those fixes rarely trickle down the chain of images that your container ultimately depends on. While your distributions package manager sets up a cron job to install fixes from the security channel automatically, with Docker you are back to keeping track of this by yourself, hoping that the app developer takes this serious enough to supply new images in a timely fashion. This multies by number of images, so you are always only as secure as the least well maintained image.

Most images, including latest, are piss pour quality from a security standpoint. Because of that, professionals do not tend to grab “off the shelve” images from random sources of the internet. If they do, they pay extra attention to ensure that these containers run in sufficient isolated environment.

Self hosting communities do not often pay attention to this. You’ll have to decide for yourself how relevant this is for you.