tl;dr I've been volunteered for SSRS, SSAS is hard, Power BI is easier and users can start to get it once you've given them a basis to work from.
This is just in my past experience and I'm just one guy... so, take someone else who has experience of many shops and add this one for flavor.
I've maintained and configured SSRS myself. But then I did it at another shop where I was a developer and there was no DBA. It hasn't needed much that way, but in the past couple of places I've never been in a place where the users could set their own subscriptions, so IT had to manage that also. It's not hard, but you may need to write up an instruction if you plan to palm that off.
As far as writing reports, our devs have done it in both locations, but I keep an eye on the sql running, and the ExecutionLog (a view in the SSRS db) to make sure nothing is performing badly.
As far as DW - I have had a couple of SSAS courses and I just don't grok it well. Partly it's because I think you really need to do it, and there has never been actual time set aside for me to create and maintain one, so the knowledge went to waste. I found it difficult to create one when I did it. If you're going that route then I'd advise trying to get a professional who has done it several times, to get the "right" data.
Instead, towards the end of my last job, and in this job, I've found we're using Power BI a lot more, and that's a lot simpler to set up. I've ended up making views that denormalize data, and created some basic data models so people can make their own Power BI reports based on that. It's not simple to pick up Power BI DAX, but it's not unlike VBA, or creating Excel formulas... and other devs and BA types are picking it up as well.