Yes indeed.
Matthew 6:7: When you pray, don’t babble like the Gentiles, since they imagine they’ll be heard for their many words.
That's a powerful argument. I'm not denying that. But it's probably less decisive than you think. The verse is sometimes translated:
"Do not use vain repetitions like the pagans".
People who have never met the Lord can fall prey to wholly mechanical, non-relational prayer. This can result in conversations like the following:
"Did you say that incantation I gave you?"
"Yes, I repeated it 75 times."
"No, the formula stipulates to say it at least 225 times to get results."
Modern charismatics don't pray that way. They KNOW the Father and are crying out for more of His embrace, regardless of how inarticulate the syllables might be. Picture your own infant child reaching out to you with his fingers, hands, and babbling. You would not despise it. You'll object, "But these are adults!". Yes. Why must fellowship and/or mutual embrace ALWAYS be eloquent?
Well, no. In the very next verse, Paul tells people not to do that, but to pray with our mind also:
1 Corinthians 14:15: What am I to do? I will pray with my spirit, but I will pray with my mind also; I will sing praise with my spirit, but I will sing with my mind also.
Unlikely extrapolation. Here's a Pentecostal reading:
"[
In the church] I will pray with my mind also" (14:15).
And here is the reasoning behind it.
(1) Tongues is by definition mind-less speech. No avoiding that. Obviously, then, God DOES cater to non-eloquent prayer.
(2) Paul did not say, "Shut up if there is no interpreter", but rather, "The speaker should keep quiet in the church and speak to himself and to God" (verse 14:28). It's okay to pray non-eloquently, even in the church, if done in a somewhat esoteric/private manner.
(3) Paul contrasted "outside the church" versus "inside the church" at verses 18-19 (where he was expanding on the verse you cited).
"I thank God that I speak in tongues more than all of you.
19But
in the church I would rather speak five intelligible words to instruct others than ten thousand words in a tongue."
Outside the church, therefore, Paul practiced non-eloquent prayer on a regular basis.
You seem to be saying that there's so much fakery that researchers might miss genuine tongues. But the sheer quantity of fakery might also suggest that it's all fakery.
And if I'm wrong, the utterly disastrous consequence would be - more non-eloquent prayer?
In my first couple of years as a Christian, I read a couple of books on the history of revival. Often the dynamics caught the participants by surprise. God suddenly didn't seem to fit in their preconceived little boxes. The modern tongues-movement also seems born in such revivals. Far from faking, the participants seemed genuinely caught by surprise. Of course, maybe every last single one of them was an excellent liar, but somehow I doubt that.