OTEL span identification breaks on external spans

[datner]

Describe the bug
I wanted to make sure that it wasn't a me-issue, so I invested untold amounts of time making sure of this.
I've instrumented two services that talk with each other through http and trying to play matchup is annoying so I ofc just forwarded a b3 header between them to connect the spans into a single transaction.
Once connected, APM loses the capability of identifying anything regarding the spans beyond their associability and errors.
Easier to see to understand
Trace from Client, nice and pretty:

Trace from Server, so much detail, how lovely:

Connected. All the information is gone:

This is not just the coloring, it's the tagging, it's the name subheader thing for requests, it's the chips tagging the transaction:

and other such things. Also, why does it say GET http:? it's supposed to say GET. or at least pull the url.route or something.

This also reminds me , shoving the entire fully-fledged url there like it sometimes does is really unhelpful. Something tagged with GET https://my.subdomain.cloudinsatnce-hash.com/path/group/fa2c8bc2-361a-427f-beed-aa2f0ae15a8e/entity/3bc8e74e-d831-4172-8196-08da6fc228a2?param1=1&param2=2&param3=jfdkl&longParam=fjjkdaohfonsaohvunklareiahfjdlsghudaflscjnauehgjkdajhjjahifhjsk might as well be untagged at all 🤔

There is no literature at all regarding anything otel in apm besides a "we have partial native support" statement so I might be missing something that is not written anywhere..

To Reproduce
Steps to reproduce the behavior:

1. connect any two traces from different resources
2. Information gone

Expected behavior
Information not-gone, or at least not completely scrubbed out

[datner]

bump??