I see ping times consistently around 10ms on my WiFi connection. However, it sometimes briefly spikes upward (while remaining green). Based on the behavior of the line, I think this might be happening when the bit of JavaScript drawing the line on the canvas staggers, rather than a blip in the connection itself. Probably a bug? It's quite noticeable when resizing the window, for example.
(I don't think it's the connection being flaky. Running `ping gstatic.com` in the terminal at the same time as the webpage is in the foreground shows a maximum time of 23ms after 180 pings.)
Oh, another bug - if you have XHR connections blocked with a tool like uMatrix, the site will assume that the time-to-failed-connection is actually the successful round-trip time, so I was getting very low numbers in Firefox. (The test in the comment above was in Chromium.)
ICMP echo requests are often rate-limited and/or deprioritized traffic on most major routers. If forwarded _through_ the router, it'll be on the slow path (software-based handling of packets) -- if forwarded _to_ the router, it'll often be on the control plane which is backed by a typically fairly slow CPU.
Ping/tracert will give you a _general_ idea of what is going on, but it is not something to definitively answer a question (i.e., a tracert may have an asymmetrical path -- travel one route to the destination, but the return packets travel another route, which you'll never see).
(I don't think it's the connection being flaky. Running `ping gstatic.com` in the terminal at the same time as the webpage is in the foreground shows a maximum time of 23ms after 180 pings.)