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
{
                LogPrint(BCLog::NET, "  getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                break;
            }
            
            
            const int nPrunedBlocksLikelyToHave = MIN_BLOCKS_TO_KEEP - 3600 / m_chainparams.GetConsensus().nPowTargetSpacing;
            if (fPruneMode && (!(pindex->nStatus & BLOCK_HAVE_DATA) || pindex->nHeight <= ::ChainActive().Tip()->nHeight - nPrunedBlocksLikelyToHave))
            {
                LogPrint(BCLog::NET, " getblocks stopping, pruned or too old block at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                break;
            }
            WITH_LOCK(pfrom.cs_inventory, pfrom.vInventoryBlockToSend.push_back(pindex->GetBlockHash()));
            if (--nLimit <= 0)
            {
                
                
                LogPrint(BCLog::NET, "  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                pfrom.hashContinue = pindex->GetBlockHash();
                break;
            }
        }
        return;
    }
    if (msg_type == NetMsgType::GETBLOCKTXN) {
        BlockTransactionsRequest req;
        vRecv >> req;
        std::shared_ptr<const CBlock> recent_block;
        {
            LOCK(cs_most_recent_block);