My best guess is that life is quite common in the universe, it is usually based on similar biochemistry to life on Earth, but it is only rarely as advanced. However, I could be wrong on any of these points.

In particular, we don't know what it takes to get life started. It might be that the watery habitats like those on Titan often have primitive single cell life. The conditions needed to evolve to higher lifeforms are only slightly better known, but it took a long time to get started.

So life on Titan is certainly possible. It may be simple, but perhaps we will be surprised when we finally get some probes into its deep oceans.

Whether life is always similar to Earth life and requires Earth-like conditions, or can appear in different forms almost anywhere, is a huge unknown. I think exobiologistes are more open minded about this than you give them credit for, but there is good reason to think that very hot or very cold environments will be less promising, especially for more advanced lifeforms that we have a chance of detecting.