The DeepMind researcher's letter elsewhere in this thread suggests to me that ECT is infinitely worse than suicide.
> They [the NHS] couldn’t prevent this. Hundreds of hours of therapy couldn’t prevent this. A large network of friends and family checking in with me constantly over the last year didn’t prevent this. Psychiatric hospitals certainly couldn’t prevent this. ECT couldn’t prevent this. The only person who could have prevented this was me.
And the memory loss he's talking about (which is indeed a common side effect of ECT) doesn't seem to be as severe as he claims to be. For one he is actually able to recall the events of his life well enough to write this letter. For another he has abused ketamine to the point of having a month long psychosis episode that ended in involuntary stay in a mental hospital, which could have had its own effects. For yet another depression itself slowly erases memories.
The memory loss was worse than they were led to believe: near-dementia levels of short-term memory loss during treatment, and still now a year of missing memories from around the time of treatment.
The treatment itself left them without time or energy to do anything whatsoever on the days of treatment, and still weakened on the days off treatment.
And, it did seemingly nothing to address their depression.
So, YMMV.
The world is a big place. Many people have tried depression treatments. You can always find someone who had a very negative experience with something.
For a counter-anecdote: I know someone whose mother was deeply suicidal and unable to function for years. Eventually they tried ECT and it was the turning point in her depression. This was decades ago and she’s still doing okay today.
Do not let internet anecdotes steer depression treatment. ECT is an extreme example. I’ve seen countless people who avoided any depression medications for years because the internet told them SSRIs were evil drugs, only to experience life changing results for the better when they finally listened to their doctor and accepted treatment.