Stamped-Pottery covered a bigger area than Channeled-Ware.
Not really, especially if you go for the typical cultural formations, not just single items. Like Channelled Ware cultures vs. Stamped Pottery cultures. Not where the pots pop up, but where dense settlement can be observed. If you go for the latter, Channelled Ware was wider spread. Because the Stamped Pottery in the narrower sense didn't cover much of the Northern sphere of Eastern Urnfield/Channelled Ware, but was concentrated in the Southern half.
Basically the Channelled Ware block was cut in half by the Cimmerian intrusion, with Mezocsat being the wedge in between - largely G?va derived, but a group of its own. North of them were Late G?va derived people, which were never completely turned by Stamped Pottery, just influenced, and South of the Mezocsat/Cimmerian wedge was Stamped Pottery.
It is pretty simple, Channelled Ware of the G?va-related kind was one huge block, ranging from Poland-Ukraine down to Anatolia-Greece, then came the Cimmerians and cut this block in half. Later came the Scythians and did the same thing (compare Mezocsat transitioning into Vekerzug). The Stamped Pottery group had way more Cimmerian and especially Greco-Anatolian influences than the Northern remains, the groups North of the Cimmerian wedge.
I wouldn't be surprised if E-V13 was there in Balkan mountain chains or so called Haemus-Rhodope mountains and expanding only in LBA/EIA up North meeting the expanding Channeled-Ware groups, and this amalgamation formed the historical Geto-Dacians and Thracians. Or call it Thracians in general.
They were overrun and there is no sign of any large flourishing population which persisted from the MBA into the EIA. It is not there. Again, the sheer size of the E-V13 population was huge, you can't squeeze it into a couple of mountains. And on what base should they began to dominate everything around them, all those newly arriving, more advanced groups from the Channelled Ware horizon? It is not there.
Now the question is, how different or whether the Channeled-Ware were different from Stamped-Ware by Y-DNA, or was E-V13 present there? I don't know.
The question with Channelled Ware is clearly not whether E-V13 was present in the Channelled Ware horizon, it must have been, the question is whether it was present in ALL of its provinces, or only specific ones. Like its possible, just possible, that I'm wrong about Suciu de Sus and a more Southern group around the Banat and Oltenia was the main core and spreader, under the assumption that Suciu de Sus/Lapus/Northern Pre-G?va did not replace them, but just gave them additional impulses.
I don't see that as a likely option, because we see the spread of fortifications and warrior burials in a more Northern style with the spread of G?va and Channelled Ware in general. This speaks for large numbers of warriors and whole tribes coming from the Upper Tisza region, in my opinion.
But this could be proven wrong, eventually, and the true centres of E-V13, the bulk of it at least, could have lived in the Southern groups of the Carpathian cremation block already before and spread from there, with the Northern groups being dominated by other haplogroups, and little if any E-V13. Again, I don't deem that likely, I think Suciu de Sus was the central early group for the spread of E-V13, but that's a possibility.
That the Channelled Ware horizon as a whole is unrelated to the LBA-EIA expansion of E-V13 is just extremely unlikely. The only even less likely scenario is that Basarabi was not full of E-V13. That's truly impossible.
As for the burial rite: This was clearly an adoption of Cimmerian/steppe rites by locals. We see that in Mezocsat in particular, where we have a continuation of G?va-like pottery, just of worse quality (less organised settlements, lack of experts and elites after the conquest, no longer as important for rituals etc.). Basically, in the East-South East, this same trend started earlier, with contacts to Belozerka in the area of Babadag. So this was simply an influence working on the Channelled Ware communities, first mainly from the steppe, later also from the Greco-Anatolian world.
That the genetic steppe-impact was overall rather low and this was rather a cultural influence can be seen in the Mezocsat locals (all females unfortunately), which score largely like I expect Northern G?va to be.