There's also ultrasonic fusing, supersonic deposition (It's got a really unfortunate acronym, cold-spray additive manufacturing), MIG deposition, etc. Metal 3D printing is a mess of different developmental avenues. Ultrasonic can do non-porous structures, but needs either post-machining or to have the foils trimmed per layer, and I don't think there are machines that aren't 7-8 figures to do it yet, as it's mostly getting interest and airtime in the Aerospace and Defense Manufacturing magazines, while MIG can do the same, but good luck getting close tolerances for waterblocks out of it. CSAM would need sealing surfaces and threads machined, but is supposed to be much lower porosity than sintered processes. They also quote some pretty low prices for print costs, but the machines are pretty expensive since they need to integrate a 6 axis robot to move the target plate and a whopping big air compressor.
Makes it fun when I get to see a new flavor of metal 3d printer, you can always be surprised by what avenues are available.
