Validation when javascript is turned off still essential?

Greetings! I’ve been practicing php for 2 years now. From procedural, oop, now I’m using doing my first project in ci.
I’m now deciding where to put myself in this dilemma. My problem is that, is it still important to consider user validation when javascript is disabled? I’m trying to convince myself to do the validation thing but the other side of me is saying ‘at this mobile/tablet generation can we still need the server side validation?’ . I’m using jquery validation at the moment.

Any insights? thank you.

Server side validation is essential - without it bots can trash your site.

JavaScript validation is there purely for the convenience of your visitors. If they have it enabled they get the error messages before they submit the form.

seems legit. thank you.