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
nNextSweep = nMinExpTime + ORPHAN_TX_EXPIRE_INTERVAL;
        if (nErased > 0) LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx due to expiration\n", nErased);
    }
    FastRandomContext rng;
    while (mapOrphanTransactions.size() > nMaxOrphans)
    {
        
        size_t randompos = rng.randrange(g_orphan_list.size());
        EraseOrphanTx(g_orphan_list[randompos]->first);
        ++nEvicted;
    }
    return nEvicted;
}
void PeerManager::Misbehaving(const NodeId pnode, const int howmuch, const std::string& message)
{
    assert(howmuch > 0);
    PeerRef peer = GetPeerRef(pnode);
    if (peer == nullptr) return;
    LOCK(peer->m_misbehavior_mutex);
    peer->m_misbehavior_score += howmuch;
    const std::string message_prefixed = message.empty() ? "" : (": " + message);
    if (peer->m_misbehavior_score >= DISCOURAGEMENT_THRESHOLD && peer->m_misbehavior_score - howmuch < DISCOURAGEMENT_THRESHOLD) {
        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d) DISCOURAGE THRESHOLD EXCEEDED%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);
        peer->m_should_discourage = true;
    } else {
        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d)%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);
    }
}
bool PeerManager::MaybePunishNodeForBlock(NodeId nodeid, const BlockValidationState& state,