You probably don't need it. It is basically like buying your own office block instead of sharing a building with a few other companies.

What if I'm thinking of monetizing (i.e. Adsense or media.net). Will I need it then?

No. Having it or not will not affect anything you are planning.

I've noticed Infomaniak doing a lot more marketing and I generally like the company and its style and whatnot.

But I'm not sure I can stick to my previous recommendation. I had a package of 10 wordpress sites with them - a couple were serious sites that I cared about and some were just one-page 'coming soon' type deals.

One got hacked, which happens, no shade on Infomaniak for that. The hack spread to the other sites, which I think (not being an expert on security) they should do better with.

I wrote to their support for help and the dude replied with a link to a pamphlet called 'so you think you've been hacked'? That is an exaggeration, but not much. I asked a very specific question and got a very general answer. I then replied 'dude' and he replied 'bro'. Not good.

I spoke to a different hosting company and their support cleaned up the hacked files and moved the sites for me. White glove service. Included in the price! No hacks since. It's more expensive but you're likely to pay one way or the other and I'd rather pay cash than in stress and time.

I still have some email hosting with Infomaniak but no websites. If you go with them you should (like with most hosting companies) invest in extra security software, e.g. Wordfence, Malcare.

Dedicated IP is useful when you need to maintain DNS hostname, e.g. you run your own mail server. Usually you require to matain A and PTR entries for your host.
This can work with Dyn DNS in theory, but I never tried.

Has anyone had any experience with Hetzner ?

https://www.hetzner.com/