I have never denied that tongues spoken in another real language for the purpose of bringing people to Christ is real. We had a Christian friend, a converted Fijian Hindu, orginally the family was from India, and he spoke in an unknown tongue one day at an evangelistic meeting. Just 4 words. After the meeting, a man ran up to him, and asked him why he didn't say he spoke Armenian. (The language, not the doctrine!). He had a napkin in his hand, and on it was written the 4 words. Do you know what those 4 words were in Armenian? Jesus Christ is Lord. The man was saved. Then the rest of his family and extended family, 27 people.
That is the purpose of tongues - real language, for the purpose of people getting saved. I have heard stories of Southern Baptist missionaries (not exactly great supporters of speaking in tongues!) speaking to a native tribe, and they heard him in their language, and the missionaries heard the unreached tribal people speaking his language. And most of them were saved! That's is what tongues is about.
What I strongly object to is two-fold.
1. Babbling as tongues, and tongues as an ecstatic experience for the person, instead of communication with God, for the purpose of bringing people to Christ, like it was on the day of Pentecost.
2. Focusing on tongues, as some do in this forum to the exclusion of the message of the rest of the Bible. The Bible has 66 books, and many chapters. Not just Acts 2. People are stymied in their Christian spiritual growth, by never stepping away from what is a deceptive doctrine, in the form it is now presented, and they lose so much of the whole message of Jesus. And the power of the Holy Spirit to transform us, instead of the Holy Spirit just putting a few words of nonsense in the mouths of those who follow this perversion of what tongues really is.
If someone speaks in tongues, and another person hears it in his own language and gets saved, then I am 100% for that. The gospel needs to be preached, and if God works in strange and wonderful ways, that is amazing! But not a bunch of people babbling in church, and no one growing, no one getting saved. I went through 15 years of that, which is a long time to be trapped and not growing, in my opinion!