lateral = sideways In other words, hiring someone on the same level.

'lateral hire' refers here to the choice of hiring someone from another firm , at the same level as they were in their old firm. So he suggests that being competitive in the market requires bringing new people in the company,who have new ideas or new ways of doing things"fresh blood" not depending on seniors working in other higher positions in parallel companies " lateral hires" to promote the level of competitiveness.