This one got 4 downvotes. I'm very, very puzzled.
It seems to me like a perfectly reasonable and clearly worded answer:
"No, it's not too late, yes, you need a teacher, neither instrument is easy".
Each of these points is, in my opinion, clearly justified.
Okay, so it also includes a sarcastic stab at Michael Nyman/Philip Glass and easy listening piano, but I have seen people get away with worse attempts at humour.
What's so wrong with it? How is that a wrong answer, a bad answer?
I am extremely suspicious that it is a matter of people simply thinking otherwise - this genuinely surprises me, as it seems to me that there couldn't be 4 people in the world insane enough to think that 26 years old is too late to start learning or insane enough to think that if you start learning from scratch at 26 a teacher is useless since you've-got-oh-so-much-time-to-waste.
I strongly feel about this not because oh-my-God-I'm-gonna-lose-reputation (if I gave a shit about reputation I could simply find 3 or 4 posts with crappy grammar or spelling to edit and regain the points pronto), but because I feel like OP might be damaged by all of this (as in, "I read a bunch of single-digit-rep users on SE saying that a teacher is useless and piano is much easier than violin, the only guy who didn't agree was downvoted into the depths of hell, now I've got RSI and I can't play anyway - what did I do wrong?").