Subsystems are now done with up front design and some degree of consensus in the BSDs, closer to the cathedral and commercial development than the bazaar of Linux. This necessarily means we are not usually at the forefront of cutting edge features. It doesn't necessarily mean we don't have features before Linux; if the idea exists in academia or other OSes enough to reason about it's reasonable to propose, design, and build. Netmap is a good example. The new FreeBSD selectable TCP stacks are another, where we avoid incremental growing pains and baggage. When these designed features hit, they tend to be coherent, usable, obvious, and lasting.
My opinion of Linux features is that little due diligence was done, especially public acknowledgement of inspiration and why one route was taken over another. For instance, the Linux KPIs are littered with questionable decisions made in isolation. epoll and the various file notification calls are examples. That attitude manifested strangely up to userland through IPC/DBus with the continued systemd drama.
A little bit of logical inference.. there are financial drivers vendors are fleeing the Linux kernel in preference of userspace (i.e. Intel's DPDK and SPDK). One is licensing, which is not an issue with BSD nor userland. The other is the rate and quality of KPI churn. Linux KPIs break all the time, switch licenses all the time, and it is a general nuisance to maintain a vendor tree whether it is open or closed source. The good side is that hopefully drivers and products end up open source. The bad side is, in many modern usages, that does not happen because GPL is not relevant to hosted services, as well as low motivation/quality/incentive/license violation for IoT type things. The BSDs start with no pretense of GPL nor flippant APIs, so it is a lot more comfortable to consume and build great products.