AFAICT, as of commit a0a422c,  we have 2 different logics to evict outbound peers : lagging-chain (`ConsiderEviction`) and (`CheckForStaleTipAndEvictPeers`). The former to sanitize out lazy/buggy peers who have never sent us a valid header and are always staying behind our tip, the latter triggered in case of stale tip due to block variance to seek a better chain by rotating our outbound peers if we already reach an outbound limit (`EvictExtraOutboundPeers`).

Block-relay-only peers were introduced by #15719. Contrary to outbound full-relay peers who provided us at least a useful header, they're not protected by lagging-chain eviction.

We actually have a comment inside `ProcessHeadersMessage` indicating the contrary behavior. We should either document cleanly that block-relay-only aren't protected or effectively extend the scope of protection to them.

Hinted during #19724 review, see https://github.com/bitcoin/bitcoin/pull/19724#discussion_r475144532
CNodeState *state = State(nodeid);
    assert(state != nullptr);
    if (state->fSyncStarted)
        nSyncStarted--;
    if (misbehavior == 0 && state->fCurrentlyConnected) {
        fUpdateConnectionTime = true;
    }
    for (const QueuedBlock& entry : state->vBlocksInFlight) {
        mapBlocksInFlight.erase(entry.hash);
    }
    EraseOrphansFor(nodeid);
    nPreferredDownload -= state->fPreferredDownload;
    nPeersWithValidatedDownloads -= (state->nBlocksInFlightValidHeaders != 0);
    assert(nPeersWithValidatedDownloads >= 0);
    g_outbound_peers_with_protect_from_disconnect -= state->m_chain_sync.m_protect;
    assert(g_outbound_peers_with_protect_from_disconnect >= 0);
    g_wtxid_relay_peers -= state->m_wtxid_relay;
    assert(g_wtxid_relay_peers >= 0);
    mapNodeState.erase(nodeid);
    if (mapNodeState.empty()) {
        
        assert(mapBlocksInFlight.empty());
        assert(nPreferredDownload == 0);
        assert(nPeersWithValidatedDownloads == 0);
        assert(g_outbound_peers_with_protect_from_disconnect == 0);
        assert(g_wtxid_relay_peers == 0);
    }
    LogPrint(BCLog::NET, "Cleared nodestate for peer=%d\n", nodeid);
}
bool GetNodeStateStats(NodeId nodeid, CNodeStateStats &stats) {