If you take everything, direct EU money plus other money from governments, foreign investments by companies, remittances from Romanians working in the EU, other aid money that flows in large amounts, not to mention market access and so on.
Anybody who rationally without nationalistic blinders evaluates that will come to the same conclusion. The idea that a Romania independent of Europe, with its shitty Post-Communist economy and the shitty companies it had could have done massively better is frankly delusional.
The idea that all foreign investment and foreign companies operating in other country is negative and explorative is simply wrong. That is the case both for individual works, company productivity and the countries economy. This has been shown to be true in tons of management studies. Insofar as Romania had issues, it its own internal corruption and other issues that they handled less well then Poland or the Baltic's.
> Why doesn't US, China or Russia want that type of help?
Russia did want the economic integration, foreign investments and so on, they just wanted it less then being an imperial power lead by a dictatorship.
If you think that is a better path for Romania then integration with the EU you are utterly braindead.
As for the US and China. The US already has its own set of alliances and cooperative agreements. It also is geographically very different and its so rich that if it was part of the EU it would be a net contributor.
China is again a dictatorship with like 1 billion people that believe they can build a system like US or the EU has themselves. And they of course did take at least large part of that package when they opened to the US and integrated the economy far more. They had foreign investment, much loser capital markets and so on.
To compare Romania Post-Communist situation with any of these, is laughable. And non of those paths are even remotely even an options.
Romania could be more like Poland, the Baltics or more like Ukraine or maybe like the Post-Soviet 'stans' just with less gas.
And of those options its perfectly clear what the right plan is.
If you have some brilliant alternative plan for Romania please share because apparently you are smarter then literally every other post Communist leader in any of those small countries. Or better yet, try to get elected on that platform. Just be aware that the massive amount of direct money and other benefits will go away, and then go watch how many people will still vote for you.
Realistic best case for that plan is that you become Belarus.