Tremulous is like an alien base.
The original people who built it did the best they could with the resources they had. But they slowly left, and over time the base was sniped and ambushed. So varied people, with varied intentions, scrambled to rebuild it.
People preferred the original layout. Some saw the acid tubes on the ground and just wanted them moved. Some wanted a complete revamp, like building a forward FOB in the middle of ATCS. Some opted to switch to the other team and start anew.
However, the core issue is that none of these options worked out in the end. Doing nothing meant inevitable loss. People stopped spawning as Grangers to do basic maintenance. People tried multiple times to revamp everything, only to waste time and effort feeding the other team via poor decision-making. It got so bad, people started to teamkill each other and forgot why they even rebuilt at all. Even the people who started anew never got to build a base that was as successful as the OG aliens.
What confused everyone was that Tremulous was never 'killed'. But it did die many times. And it came back just as many times- but the players did not. An alien base without it's grangers spamming acid tubes, players sniping as ADV Dragons or clan members sharing credits to Tyrant rush the hallways- is no 'proper' alien base at all.
Tremulous as we remember has left, but the memories we've had will always stick around. Tremulous now sits quiet. Waiting for the few, rare days people remember to join back in.