I can now confirm that, if a PowerApps forum section was instituted, I myself would be active in it. How soon I will get to the point where I can answer questions, that I'm not sure, but I'll try my level best!
As far as why it is the 'next best thing', I look at it more as a matter of: "it IS the next big thing, therefore, the best thing [for me anyway] is to get on board". Why anyone thinks it deserved that spot is a separate discussion, and one which I have no thoughts on at the moment. But it got that spot, so....I'm learning it at my company.
I recently created a Power Automate flow that automatically sends email notifications based on when a new record is created in a Sharepoint list, then updates the list item(s) with the DateSent. Quite handy for those of us whose corporations have, for whatever reason, denied us hardcore SQL Server development capabilities (SSIS, SQL Agent, etc) but are quite OK with Flows.
Power Apps seems to be at its best when the host organization has an extensively well-developed, tightly knit integration with all-things-Microsoft. For example, there are simple expressions you can use in PA to, say, return the value of the current user's Manager, or that Manager's email address. Imagine that being built right in without you maintaining any type of Users table, or trying to query LDAP!
Combined with Flows, it's quite powerful.
Not being able to write free flowing code is extremely annoying at best, but you can write powerful expressions and combine them in sequence as much as you like: expression1;expression2;expression3. The expressions can "do" things- like set a variable, return a table/collection, send an email, etc.