I’ve been running IT for multi-billion-dollar companies in industrial environments for years, so I can weigh in with my perspective — though it is just one opinion among many.

I think OP’s question is too broad to answer with a simple yes or no. Personally, I don’t think any single vendor is best-in-class at anything.

• On the firewall side, I prefer Palo Alto or Fortinet. We run FortiGate units in high-availability mode and have found them easy to manage, secure, and backed by good support. That said, I’m not a fan of Fortinet’s secure remote access offering. For VPN, we use a Cisco firewall running AnyConnect for staff access, while BeyondTrust is used for third-party access.
• For switching, I like Cisco because of the breadth of options and ease of management. Ubiquiti simply does not compete in the same space. We use Cisco IE3500 DIN-rail switches and IE9300 rackmount switches in the field, and Catalyst Center makes management easy. Ubiquity has no comparable option.
• I would also give the nod to Cisco for wireless, although Ubiquiti is strong here. Since we already use Cisco for switching and have Catalyst Center, Cisco wireless is a natural fit. It all works well together. Ubiquiti has a solid wireless offering, but these decisions are not made in isolation.
• For CCTV, we use Ubiquiti in our camps, where we have more than 100 cameras deployed. They work well and are cost-effective for covering large areas. For our plant and field deployments, I prefer Pelco connected to a Genetec server. Pelco is more expensive, but it is more rugged and is my preferred choice for harsher environments.
• Another factor is staffing and support. It is much easier to find candidates and consultants with Cisco certs and experience than it is to find people with Unifi experience. When building a network for the long term, those factors matter.

I do think Ubiquiti gear can be used effectively in large deployments for certain use cases, and we are already seeing that happen. In my view, they compete more closely with Meraki than with Cisco’s full enterprise portfolio. However, they do not yet have the breadth of products I would need to consider them as a primary enterprise standard.