That’s not entirely true and is mostly propaganda pushed to create a “Ukrainian identity”.
To put it simply, the famine was primarily impacting Cossacks, which were throughout southern Russia at the time. You can look up the famines and see it’s not specifically targeted.
Though I do grant you, collective farming was the issue and it did have an undue impact in Ukraine.
Didn't the Ukrainian famines happened because the URSS was also exporting grain at the same time to capitalist countries, in exchange for industrial development?