Good Morning all
Not sure how, but I missed the posts on this page. My apologies for this!
Trainz: A New Era will need all SpeedTrees to be re-exported/recompliled in SpeedTree V6. This is, unfortunately, an issue with SpeedTree rather than Trainz. We either upgrade to V6, and need trees to be recompiled, or remain at V5. We feel that V6 will suit our needs better, being the most current version of SpeedTree that we could use. This was noted previously, earlier this year, but not sure when/where. We have been in contact with several SpeedTree creators to assist with upgrading their SpeedTree assets, however this will be up to them to explain their plans if any (as Gawpo50 has done above

).
As to what will happen with this, we really need to wait and see, as it does in part depend on what creators decide to do.
As to the issue with the DLS uploads. As noted by a few people, there are trees that are (or at least may be) legitimate, that appear to not be so, whilst there are others that go the other way. At one point, we did have legitimate trees requested to be removed because it was believed that they may have been pofig's, it was only when we looked properly at them that we found that they were not the same trees (note, this is why we need comparison assets to be provided to us). I'm not sure the community would like us to ban all SpeedTree assets from the DLS because they
may look like Pofig's (and in turn
may not be legitimate), as this is the only viable option if we want to go to an extreme (we can't have someone manually checking every upload against EVERY asset from EVERY creator of SpeedTree assets just in case).
As noted previously, the only people who know with 100% certainty that an asset was uploaded without permission is the original author, and the uploader. Everyone else is just guessing...
If you as a creator wishes to ensure that your artwork is not being redistributed, then you will need to put in the work to check it. This is the case with any artwork (or copyrighted item), not just Trainz content... Otherwise I could walk up to an art gallery, and demand all the artwork be taken down, because
I think they may be breaching copyright... If you, as a 3rd party, wishes to help, then report any possible cases to the creator (this applies to any copyrighted items).
Same goes with the DLS. Imagine someone reporting, say, all of clam1952's uploads (as an example here) as illegal, and having them removed. Or at least making N3V spend several days checking them (1200 assets, that's a lot of assets to go through and look at, and then go searching for the 'original' assets to compare them too), then contacting the supposed author (or original author, if we're talking reskins/etc), then the author having to go through them all and outline their origins (we would need a per-asset explanation, so as to cover it properly). Gets very messy very quickly if you try to go the other way...
Or we just ask the authors to report them to us as they find them (
and as above, if you as a fellow community member thinks an asset may not be legitimate, contact the original creator! - note, made this 'bold' as it seems to be missed every time this topic comes up), with the relevant information. And for the author to actually check that it IS their content that has been uploaded...
Regards