If the packet loss starts at your wifi router, or your ISPs router. Or the next hop after you ISP. That all gives you a bit of an idea where the problem likely is. I solve problems like that all the time.
The only way to reliably isolate packet loss to a hop on the path is to have a destination for testing where packets pass through that hop and is in its bailiwick which doesn't perform rate limiting or policing of ICMP traffic.
If D has 1% loss and B and C have 50%, is it fair to say A=0, B=1%, C=1%, D=1%?
MTR display of loss is indeed confusing, but when weird things are going on it can be helpful just stare at it a while to see what's going on. Trippy looks fantastic, and I need to play with it, but there are cases where I just want to stare at the path loss for a while.
There's no way to influence the TTL on TTL timed-out responses, is there? That'd be pretty cool if there were some way to get the return path of the intermediaries to reply.