IMHO triggers are almost always best avoided. There are some exceptions but most of the time you want changes to be explicit not happening "by magic" behind the scenes as a side-effect of something else.
I am not sure it necessarily would be that bad. After all foreign keys are implemented with triggers and they are usually fast enough. You just need to write trigger functions which are fast enough.
It is possible, that's how I do it, and it doesn't really affect performance at all. You just don't do it real time, the triggers just kick an id into a queue and you have a background task work the queue updating the materialized table from the view it's a copy of just for the id's in the queue.
