I have about 20 years of data collected, both memes I've saved as well as original content. Those that already have the text, I have always zeroed out the font size and retyped the text so it registers for the bots to determine. This way, if there is a taboo word in the text, the bot can properly assign the NSFW tag, as Imgflip has chosen not to make a list of the taboo words available. Prime examples of these are the PUNography memes I post. These are from a website I ran a few years back. This has never been a problem before. Maliciouness? No, it's to keep the aesthetic of the actual meme. In situations where a previous meme was used, I add the originality in the title section. It's known as the flow: it works well alongside the meme, but is distracting within the meme.
Original content. Yes, it is nice that every post here were original. But then, what would be left on the plate if it were restricted so. 99% of the GIFs here would not be posted, and reposted. The key to Imgflip is the number of users that visit and read what's posted. The number of Pro accounts is rather small considering, so that the number of people that visit is based on is what drives the advertising dollar.
I notice that this week, I have had four posts that never were featured. I can assume that the animated GIFs are because of the crack down on original content. Interestingly enough, similar posts only a week before were gladly featured, and have been featured without a problem for some time. Taking this crackdown on my posts shows more a personal initiative of one mod than anything else. You've tipped your hand by making the threatening comment as you pushed this post back to submissions. Your discussion is unusual to find on a post, as it would be better suited in a private conversation with your superiors.