Personally, I don't want them to expose anything. The RTT on my packets is yet another piece of metadata capable of being abused.
In addition, I hope that the whole QUIC thing is a nice reboot of actually getting end-to-end connectivity back on the Internet so we can get some protocol experimentation moving again.
CPE (the WiFi router or similar in your home) often adds delay because a few megabytes of RAM is cheap and the people who built it don't understand what they're doing. This is called "buffer bloat". But inside the network core this rarely comes up.
Queueing them up instead makes some artificial benchmark numbers look good but is a horrible end user experience, so you should never do this, but lots of crap home WiFi type gear does.
So, as I said, bandwidth limits and delay are different. The canonical "station wagon full of tapes" is illustrative, it has _tremendous_ bandwidth but _enormous_ delays. In contrast a mid-century POTS telephone call from London to Glasgow has almost no delay (barely worse than the speed of light) but bandwidth is tightly constrained.
I have an RTP stream running from India to Europe at the moment, 3000 packets per millisecond, so 0.33ms between pacekts. Typical maximum interpacket delay is under 1.5ms, looking at the last 400,000 seconds of logs, 200k are 1-2ms, 170k are 0-1ms, and about 4-5k on the 2-3ms gap, 3-4ms gape, etc. Less than 1% does interpacket delay increase past 10ms.
I currently have a difficult provision that for a variety of reasons I can't use ARQ on. To keep the service working I have 4 streams going, over two routes, with timeshifting on the streams to cope with route-change outages that tend to sit in the 20ms range. FEC is meaningless at these bitrates.
RTP is fine for delay and re-orders, but it doesn't cope with drops. I was at a manufacturer's earlier this week and said that I've experienced dual streaming skew of over 250ms (we had one circuit presumably reroute via the US), and I laugh at their 150ms buffer. Dual streaming can still fail when you have both streams runnning on the same submarine cable though. Trust me, intercontinental low latency interoprable broadcast IP on a budget isn't trivial
Moreover, since your specific use case is not interactive conferencing, but IPTV, there would be no problem in incrementing even more the FEC ratio, at the cost of a small decoding latency.
And yes, this use case is interactive conferencing, where we aim to keep round trip delay from Europe to Australia down below 1 second.
I have been trying to figure this out for a while but information aren't really available.
For example, let's say we can move 10Mbps, and we've decided to use 10 megabytes of buffers to make our new WiFi router super-duper fast. Do a big download, the buffer fills with ten megabytes of data, that's eight whole seconds of transmission, now the latency of packets is eight seconds, so that's 8000 times larger than your "I assume less then 1ms".
{Edited to correct numbers}
e.g. You are syncing gigabytes to Dropbox. A poorly designed router will continue to accept packets far past upstream capacity. Now that's there's 2000 ms of bulk traffic in the router's queue, any real time traffic has to wait a minimum of 2 seconds before getting out.
1) Drop -- despite total trafic being only 10mbit a second
2) Queue -- introducing a delay of 30ms.
In reality you'd put latency critical applications (voip etc) at the top of the queue so the pcakets get transmitted without the delay, and your facebook packets get delayed by 31ms rather than 30ms.