Is it ok to have no workplace friends

I have none. Across three companies that I have worked in, none. I work with 9-5, shut out mindset. I'm not available after paid work hours.
Also I just don't know what to talk other than work, yes/no/okay.

I agree, things would have been easier especially in job searches but well that's how it is

At least try to make friendship with genuine people in the office or people who are on good terms with you. In the future, they might help you.

If working for more than a year in a company, one should make efforts to make friends. It will succeed only with like minded people and cannot be forced. You will learn about different cultures as people in office will not be a homogeneous group. Even after leaving company, you can always be in touch.

Irrespective of like minded or not, good friends or not, having good contacts is necessary especially after 10+ years experience as job switching is easier with networking and referrals.

At the end of the day, people in your office are also just that, people. You are likely to run into some you'd connect with, and then some you'd absolutely despise. I've formed a few genuine friendships that have outlasted my stay at that org. It gets easier if you have people from a similar education background / age etc.

Be open to becoming friends, don’t be deliberate in declining invites, or rejecting advances for friendship. Also, don’t force friendships. Be extremely kind to new joiners.

Also be very curious and ask a lot of questions instead of assuming/holding back.

I’ve done all of these and I find it impossible not to have friends at work.

I usually tell my team members. You are not here to make friends. You are here to deliver on your KPI's, if it requires you to call out BS then call it out. You can be friends but not at the cost of your work and people will respect you for it. I am personally friendly with a few colleagues and meet them sometimes outside work but that's it. I usually keep in touch with people who intellectually stimulate me.