Say a university is hiring a science faculty member. Only the search committee interviews the job candidate online. Then the candidate gives one research presentation online. The candidate is then offered the job, but they are not invited to visit the campus first or given any kind of virtual campus visit. They are also not given any contact information to talk to any of the other faculty they will be working with. Are these red flags, or is this how hiring faculty works post-COVID?
You should really give your country or geographic region. I throw something out based on my perspective (I have tenure in the US and taught in Uruguay, El Salvador, and India) assuming that you need some feed-back quickly.
Ask yourself whether you would be confident to take a job as an accountant or software engineer under these circumstances in your country.
If the job is temporary such as for a year, this procedure makes sense. Your duties would be restricted to mainly teaching with maybe a small research / service component. The cost of bringing several candidates on campus would then exceed the benefits for the university. As a candidate, you get one year of teaching at a university out of it, but you would presumably start looking for another job as soon as you get there. Besides a job for a year, you would then have a source of reference letters and a track record for teaching at a university.
I got my first job in Mathematics in the US this way as a fresh Ph.D. from Germany. Apparently, it worked out well for both parties. They would have offered me a permanent job if they could and were helpful getting me another, tenure-track position.
Now, if this is for a full-time tenured or tenure-track position (in the US) or if this is expected to be a life-long position, then they did not scrutinize you well enough. But they are also not fair to you, because they do not allow you to gather enough information. It could be that they have no money allocated for a proper search (e.g. because someone left unexpectedly). In any case, if they offer you the position, you might ask to visit them before you make a decision. If you do not have the money, you might just talk to your future colleagues.