Everyone from your fiber provider is getting fiber-class latency, regardless of the plan's max speed. The fiber ISP in my area uses 10 gig ONTs for everyone, and limits each plan's speed with PPPoE. This is pretty common, and likely yours is doing the same.
On the other hand, everyone using the cable provider in my area, whether on their fastest or slowest plan, is getting the same tens of milliseconds of DOCSIS 3.1 latency, on a node that has tens to hundreds of gigabits of bandwidth but is using TDMA and FDMA to share it between a few hundred users.
My point is that the lowest-tier subscriber from your fiber ISP is getting magnitudes lower latency than the top-tier subscriber from my cable ISP. If either of the switch plans, but don't switch ISPs, they'll have the same latency.
Everyone from your fiber provider is getting fiber-class latency, regardless of the plan's max speed. The fiber ISP in my area uses 10 gig ONTs for everyone, and limits each plan's speed with PPPoE. This is pretty common, and likely yours is doing the same.
On the other hand, everyone using the cable provider in my area, whether on their fastest or slowest plan, is getting the same tens of milliseconds of DOCSIS 3.1 latency, on a node that has tens to hundreds of gigabits of bandwidth but is using TDMA and FDMA to share it between a few hundred users.
My point is that the lowest-tier subscriber from your fiber ISP is getting magnitudes lower latency than the top-tier subscriber from my cable ISP. If either of the switch plans, but don't switch ISPs, they'll have the same latency.