I can provide some extra context on this, since this happens to concern my employer.
At a super-duper-high level, FlightAware has historically only tracked flights for which we had a flight plan of some kind. The reason for this is that without the "context" provided by a flight plan, it becomes a lot more difficult to string together arbitrary position reports in a meaningful way.
Example: N12345 files IFR from KLVJ to KNEW, departing 1700Z. When the flight plan is filed, we get that data and store it. 1700Z rolls around, and at 1702Z we get a position for N123, just off KLVJ and climbing. Since we have the flight plan, we can be reasonably assured that this position will be followed by more positions, and that all these positions can be combined into a "flight." Furthermore, if at some point mod-flight we don't get positions for a few minutes, we can assume that those positions will resume in short order, and when they do, we keep assigning them to that flight.
VFR flight following essentially worked the same way for us. You didn't file IFR, but when you got flight following ATC might put your flight data into the national airspace system, which meant that we received it just as if you'd filed IFR, and it was basically identical to the above scenario. This is where the local vs. "national" (I dunno the technical term) squawk code issue came in. In the former case, you didn't end up in the NAS, in the latter, you did.
Without the context of a flight plan, it becomes a lot tougher to make sense of position data when it comes in. It's one of those tasks that seems relatively easy for a human, but is challenging to express programmatically.
The change that the FAA made earlier this year was to essentially stop providing flight plan data at all for VFR flights, even if they were entered into the NAS. So where we used to semi-reliably get flight pan data when you got flight following, now we get diddly squat. The result, from your perspective, is that VFR flights no longer appear. Unfortunately, it's out of our hands.
There is, however, a solution on the horizon. We've put a substantial amount of work into solving the problem of tracking what we call "position-only" flights - that is, flights without a flight plan. This feature is somewhat functional, but still not 100% reliable, not to the point that it's ready for the public. When it works, it looks nice, but when it doesn't the results can be pretty comically misleading.
When position-only tracking is released to the public, you'll be able to track your flights even more reliably than before. Unfortunately, though, there's no real timeline for when that will happen.