Yes, for sure. As a defender, you have two main tools: dummy packets (bandwidth) and delaying packets (latency). Padding-only defenses will indirectly delay normal (non-padding) packets by filling the connection with padding. You want to explicitly block outgoing traffic and try to account for congestion to minimize wasted bandwidth.

This is tricky. We have hardly started dealing with traffic analysis issues in protocols. In general, we have spent the last decade+ getting encryption sort of right with amazing efforts like TLS 1.3 and WireGuard, etc. Expect another decade for traffic analysis.