You can create rules based on the content of the notification to group different notifications together as one, to delay them, to change the ringtone or to dismiss them all together.
You can also automatically click a button inside of a notification if certain requirements you define are met, you can stop the same app to send many notifications within a set amount of time (like when someone is writing a lot in a WhatsApp group then you only get one notification per minute for that group)
It’s way more than just focus mode
Shiftphone is a good alternative but it’s also on the more pricey site.
You could get lucky and get a used one for cheap? Since the battery can be replaced and is usually the only part needing regular replacements every couple of years you should be fine?