I don't believe anyone here has appealed in the last couple of years.
I only recall about 3 people appealing in the 9 years I've been on this forum. I remember that two of those appeals were justified because their visas were refused even though they sent every single required document, but the ECO overlooked them and refused the visa when they shouldn't have. Therefore they won their appeals.
I also know of one other person recently who could have appealed, since UKVI made a mess of their application and claimed they never received the extra documents they requested (even though they were sent twice), resulting in 8 months of waiting for the visa and then a refusal based on not receiving the documents that were in fact sent, when it should have been approved (they applied from Europe as they were living there at the time). However, this person didn't want to waste even more time waiting for their visa and didn't want to go through another year apart from their partner, so they returned to the US, applied again from there and got the visa in 2 days.