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
const auto last_request_time = GetTxRequestTime(gtxid);
                if (last_request_time <= current_time - GETDATA_TX_INTERVAL) {
                    LogPrint(BCLog::NET, "Requesting %s peer=%d\n", inv.ToString(), pto->GetId());
                    vGetData.push_back(inv);
                    if (vGetData.size() >= MAX_GETDATA_SZ) {
                        m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::GETDATA, vGetData));
                        vGetData.clear();
                    }
                    UpdateTxRequestTime(gtxid, current_time);
                    state.m_tx_download.m_tx_in_flight.emplace(gtxid.GetHash(), current_time);
                } else {
                    
                    
                    
                    
                    
                    
                    
                    
                    
                    
                    
                    
                    const auto next_process_time = CalculateTxGetDataTime(gtxid, current_time, !state.fPreferredDownload, false);
                    tx_process_time.emplace(next_process_time, gtxid);
                }
            } else {