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
if (state.m_tx_download.m_check_expiry_timer <= current_time) {
            for (auto it=state.m_tx_download.m_tx_in_flight.begin(); it != state.m_tx_download.m_tx_in_flight.end();) {
                if (it->second <= current_time - TX_EXPIRY_INTERVAL) {
                    LogPrint(BCLog::NET, "timeout of inflight tx %s from peer=%d\n", it->first.ToString(), pto->GetId());
                    state.m_tx_download.m_tx_announced.erase(it->first);
                    state.m_tx_download.m_tx_in_flight.erase(it++);
                } else {
                    ++it;
                }
            }
            
            
            state.m_tx_download.m_check_expiry_timer = current_time + TX_EXPIRY_INTERVAL / 2 + GetRandMicros(TX_EXPIRY_INTERVAL);
        }
        auto& tx_process_time = state.m_tx_download.m_tx_process_time;
        while (!tx_process_time.empty() && tx_process_time.begin()->first <= current_time && state.m_tx_download.m_tx_in_flight.size() < MAX_PEER_TX_IN_FLIGHT) {
            const GenTxid gtxid = tx_process_time.begin()->second;
            
            
            tx_process_time.erase(tx_process_time.begin());
            CInv inv(gtxid.IsWtxid() ? MSG_WTX : (MSG_TX | GetFetchFlags(*pto)), gtxid.GetHash());
            if (!AlreadyHaveTx(ToGenTxid(inv), m_mempool)) {