Not quite. As a Romanian speaker I can’t understand more than very basic Italian. Perhaps Spanish is slightly more understandable but still not to a 90% level for sure.
Romanian kept its case system unlike the other Romance languages by virtue of ending up in the Slavic sprachbund. I'd wager that there are Slavic loanwords as well?
> A statistical analysis sorting Romanian words by etymological source carried out by Macrea (1961)[88] based on the DLRM[99] (49,649 words) showed the following makeup:[89]
> 43% recent Romance loans (mainly French: 38.42%, Latin: 2.39%, Italian: 1.72%)
20% inherited Latin
11.5% Slavic (Old Church Slavonic: 7.98%, Bulgarian: 1.78%, Bulgarian-Serbian: 1.51%)
8.31% Unknown/unclear origin
3.62% Turkish
2.40% Modern Greek
2.17% Hungarian
1.77% German (including Austrian High German)[97]
2.24% Onomatopoeic
If the analysis is restricted to a core vocabulary of 2,500 frequent, semantically rich and productive words, then the Latin inheritance comes first, followed by Romance and classical Latin neologisms, whereas the Slavic borrowings come third.