The alternative is that paid government officials and government/EU research institutions supply their research results to lawmakers and refuse to read gray papers from corporations or big civil influence groups. That's all well and good as part of the mix, but on its own, a very narrow viewpoint in a complex society. (The fight over who is nominated to these research jobs becomes even more political.)
Removing possibilities of corruption from MEPs means removing their power and moving it into deeper government bureaucracy where it is harder to spot. Now you have non-elected people who work whole their life in government using more power.
Yes exactly academics and researchers not dealing with the real world should not decide policy.
Academics and researchers are prone to groupthink and monocultures. To quote a form of Sayre’s law “Academic politics are so vicious because the stakes are so low.”.
Researcher’s policies might be disastrous for society or industry yet they’ll often be insulated from any consequences, even just to their reputations.
The things about unelected career bureaucrats is that they usually have no legal mechanism for directly benefiting from the outcome of their policy suggestions. They can't even accept lunch from outside groups without facing disciplinary action. I would prefer those people have the power of opinion rather than someone who benefits directly or has a perverse incentive to accept "campaign money" in order to further a change in law.