Yes, but enabling mailing list mode (if I understand correctly that warning also seen in your screenshot) completely shuts down almost all Discourse functionality (which threads you find interesting, watched tags, 1st post watching etc).
In other words, it is mostly only useful if one never uses web interface (!!), and prefers to use Discourse as headless mailing lists of the past sending all messages in all threads to you.
Which is not my use case; I would like to keep using Discourse as web forum, watching only some threads (and receiving email only for them), but also have e-mails that I already receive of watched conversations also include my posts (so the saved e-mail threads are actually readable).
As I’m only interested in like 1% of the threads that I watch; I definitely do not want to receive 99% of the other uninteresting threads just so I would receive 0.1% of my own posts too (which enabling mailing list mode would do, if I understand correctly?)