ehmmm... From the recent Bloomberg article I read the Russia claims ~6K dead and some unspecified western experts estimate it rather ~15K. Now USA lost ~60K in Vietnam. Sorry, that is not "as many or more". Nowhere near.
15k KIA mean 45k casualties. Now, this might be a bit too low: 7k funeral reported on Russian social networks when most of the armed forces aren't from areas with cheap internet access.
They are mobilising to increase presence and unit rotation along the frontline, without having to decrease their presence along their borders with other countries.