'Russian Developers' are material to the development of the Russian economy, which is the basis for which the war is projected.
Sanctions could very well spread into software in which FOSS would likely be a part of it, and the terms of the licensing may not really matter.
It's for the same reason that Intel, Nvidia and a host of others have dropped shipments, at least for the time being.
How far would you follow that logic? Which Russians should be harmed, in your opinion, and how much?
No need to harm 'ethnic or cultural' Russians
Just Russian citizens with wealth or those insidevthe legal jurisdiction of Russia.
BTW, you should know that sending money to Russia is almost an impossibility as it is. For example, living in Russia, I couldn't accept a consulting job from Kazakhstan because we couldn't figure out a way for them to pay me.
We have proportionality, we draw lines, we target individuals differently that government than industry than high tech that commodities than consumer services etc..
In my view, we should be doing much more, borderline embargo.
Russian military gains in Ukraine will never, ever be conceded by anything other that either force or 'near collapse' of economic conditions (or overthrow of regime).
Russia can 'put bodies' in Crimea, NW of Kyiv basically to act as targets forever, Kyiv doesn't have the manpower to route them even if they can defend themselves.
Strategically, this implies Russia can merely endure some local pain and make permanent territorial gains.
In 10 years, this war might be like Afghanistan or Iraq, something that '55-75 demographic' watches on the news but otherwise everyone else is busy on TikTok - which is what Putin wants.
He can definitely win the war of attribution because he has a much longer frame view of things, and is willing to pay the cost of 'No Volvos or Starbucks for 25 years'.
Other nations that play the long-tame (like China) are watching.