That's still pretty low. In the us at a top tier, which you'll need for most tenure track positions you're expected to have about 5 first authors in five years as a trainee and moving forward into a postdoc a pace of about 1.5 to 2 would be good. Strategic timing by having a really high profile paper come out from grad school around when you're finishing your postdoc probably also helps.
But as I indicate in a direct response I don't think any of that really matters either
Everyone's talking about publication count. Is the quality (influence, number of citations, any other relevant metric) of those publications really so irrelevant?
No, and yes in a way. The quality of the venue matters a lot, and many people seem to obsess over h-index values, which quantify the citation count and journal impact factor. But in my opinion these things are useful but flawed heuristics for the actual importance or impact of research work.
Imagine you are on the professor search committee. You get inundated with 500 applications, many from jokers with no chance from a diploma mill who just spam every search committee. How do you filter so many applications?
But as I indicate in a direct response I don't think any of that really matters either