Im creating this so this does not fade. During investigation into related issue(WFLY-20983) this things came to light.
1. web sockets are not defined as web components - this might be because this kind of differentiation came to life ~5 years after WS integration
2. deployment phase of web sockets is late compared to other elements

#1 POC https://github.com/baranowb/wildfly/tree/WFLY-20983 - though it has drawback of breaking some CDI integration
#2 UndertowSubsystemAdd.java#L127
which roughly translates to:

POST_MODULE_UNDERTOW_WEBSOCKETS : 11776
vs
POST_MODULE_WELD_COMPONENT_INTEGRATION: 2048 - "integrate" weld into components
vs
POST_MODULE_JSF_MANAGED_BEANS 768
and
PARSE_WEB_COMPONENTS 8200 PARSE - which spawns for instance servlets

NOTE: parse phase happens before module.