The second map is a language map from 2014 for 2001:
https://www.polgeonow.com/2014/03/ukraine-divisions-election-language.html
Looks a lot like Hitler’s justification for invading Sudetenland. Appeasement of that local bully ended up costing 50-60 million lives. Learn the lesson of how appeasement doesn’t work. If that issue was such a big deal then Russia never would have signed the Budapest Accession to the NNPT.
I would note that language is not the only definer of nationalism.
In the 1800s there were many Irish who spoke only english not Irish Gaelic, but they felt Irish.
Similarly here there are many Russian-primary speakers who are Ukrainian.