I would like to agree with what the Electrum Developer Thomas Voegtlin said that bitcoin unlimited is not a good idea since if we really look at the hardfork it has many bugs and it not feasible for bitcoin at this moment. But later in time if bitcoin is ready for a hardfork then maybe that will be the time that bitcoin unlimited will come into the picture.
I dont think [Bitcoin Unlimited] is a good idea, Voegtlin said - he never said he as 100% sure. "I don't think" implies one isn't 100% sure but somewhat on the fence so to speak.
It means that he's leaning towards it being a bad thing, and chances are a guy like this knows what it is and has done his research, so he's going to have an opinion formed. If he said "I'm not sure if it's a good idea", that would be way more indicative of him being on the fence. I would want to hear how he said "I don't think [etc]" because tones mean a lot more than just text. If he's really unconfident in it, he can make it easily known.