He is actually right, it doesn't matter if it's hosted on an external site or not, if you are the owner of the forum you can be sued for copyright infringement if someone posts a copyrighted picture. Of course it matters a lot where the server is located.
Not if the link is to an origional post. It is like posting a URL.The presence of the image is only virtual. The image file is not on the bitcointalk server - only a link to the image.
Removal of the image from the linked site will result in the url displaying 
Such site can also block external access to the image.In the country where I live it is not considered infringement. It is also not disallowed by the bitcointalk rules.
...and that is not even getting into the "fair use" argument or the fact that most, if not all of the images that were linked to are in public domain with no distinguishable ownership.
A lot of the memes are generated on meme makers using royalty free stock photos.
Crazy countries can make crazy laws. But since I don't live in them or plan to visit they have no jurisdiction over me. If those countries attempt to enforce those crazy laws outside of their own country it may well be breaching the constitutional laws of the country that I live in.
In the majority of civilized countries - linking and framing is not considered copyright infringement.In large part, linking and framing are not held to be copyright infringement under US and German copyright law, even though the underlying Web pages are protected under copyright law. Because the copyright-protected content is stored on a server other than that of the linking or framing person (it is stored on the plaintiff's server), there is typically no infringing "copy" made by the defendant linking or framing person (as may be essential), on which to base liability. Some European countries take a more protective view, however, and hold unauthorized framing and so-called deep linking unlawful.
The European Court of Justice's binding ruling in 2014 was that embedding a work could not be a violation of copyright:
The embedding in a website of a protected work which is publicly accessible on another website by means of a link using the framing technology
does not by itself constitute communication to the public within the meaning of [the EU Copyright directive] to the extent that the relevant work is neither communicated to a new public nor by using a specific technical means different from that used for the original communication
https://en.wikipedia.org/wiki/Copyright_aspects_of_hyperlinking_and_framingAs long as Bitcointalk follows the DCMA guidelines they have nothing to worry about.
loads of your posts pages and pages are just content that you did not create I mean most pages of you history are filled with content that is not original.... you are probably net negative here so don't start talking to those on another level in terms of contribution to this forum.
why don't we just tell noobs to copy and paste text to an image and post it here linked from somewhere else how will that be any different ... filling up tons of spam all over the place that bots can do in seconds.... this kind of implanting of other peoples content is equally as bad if not worse and yes could actually have legal implications now or in the future.