Email is honestly not that hard to get right, but you do have to get a lot of stuff configured correctly for everything to work well. I've never had a lot of problems with blacklisting and at one point, was running about 48,000 messages per day sending marketing emails (ecommerce sites, to subscribed users) and transactional emails. Deliverability issues were few and far between, and most often were caused by MS Exchange admins at distributors (where we would send orders via email) who just didn't understand how the internet worked (like blocking all domains that weren't .com, .net or .edu). My favorite was one who blocked .io because he personally only got spam from that TLD.
On the whole, just use a service makes sense in that the time you spend on email probably could be spent on things that make money. If you have an app that sends a lot of emails, understanding how it all works can be a very useful skill, too. So is learning to work with admins at big service providers.
On the whole, just use a service makes sense in that the time you spend on email probably could be spent on things that make money. If you have an app that sends a lot of emails, understanding how it all works can be a very useful skill, too. So is learning to work with admins at big service providers.