Could it, really? I know that nginx has some builtin load balancing, but unless it's vastly vastly changed in the past few years, it's still a LONG way behind haproxy for load balancing.
nginx is an excellent high performance webserver, which is something F5 don't really have. It is (or was, at least) at best a mediocre load balancer, with all sorts of limitations at the sort of scales you'd usually use an F5 box for. While it's probably fair to wonder how much more work will be put into the LB feature-set of nginx, I hope that this will be counterbalanced by increased funding for the core feature of being a superlative webserver.
nginx's worse-than-F5-and-haproxy load balancing was great for where I was using it. And from all reports, F5 would have required a full engineer to do configuration, compared to about 1/4 of an engineer for nginx.
nginx is an excellent high performance webserver, which is something F5 don't really have. It is (or was, at least) at best a mediocre load balancer, with all sorts of limitations at the sort of scales you'd usually use an F5 box for. While it's probably fair to wonder how much more work will be put into the LB feature-set of nginx, I hope that this will be counterbalanced by increased funding for the core feature of being a superlative webserver.