Weird numerical instability controlled by axis increment

### Describe the bug
See attached, possibly related to #1441

**Code**:
It's in the screen shot, although I'll put the whole code here (the only difference is the axis label step)
```
class GraphExample(Scene):
def construct(self):
#axes = Axes((-10, 10, 5),(-10, 50, 10))
axes = Axes((-3, 3, 5),(-1000, 10, 100))
axes.add_coordinate_labels()
self.play(Write(axes, lag_ratio=0.01, run_time=1))
first_graph = lambda x: 2**x
first_label = "2^{x}"
graph1 = axes.get_graph(first_graph, color=BLUE)
label1 = axes.get_graph_label(graph1, first_label)
self.play(ShowCreation(graph1),FadeIn(label1, RIGHT))
self.wait(3)
graphs_and_labels = [
#(lambda x: (1/2)**x, "(\\frac{1}{2})^{x}"),
#(lambda x: (2**((-3*x)+1))-3, "2^{-3x+1}-3"),
#(lambda x: ((1/2)**((x/2)-4))-1, "(\\frac{1}{2})^{(\\frac{x}{2})-4}-1"),
#(lambda x: (-2**(2*x))+(19/93), "(-2^{2x})+\\frac{19}{3}"),
#(lambda x: (2**(x/4))-3, "2^{(\\frac{x}{4})}-3"),
(lambda x: -((1/2)**(-4*x)), "-(\\frac{1}{2})^{-4x}")
]
for graph, label in graphs_and_labels:
graph2 = axes.get_graph(graph,color=BLUE)
label2 = axes.get_graph_label(graph2,label)
self.play(ReplacementTransform(graph1, graph2),FadeTransform(label1, label2))
self.wait(3)
graph1 = graph2
label1 = label2
```

**Wrong display or Error traceback**:
n/a

### Additional context
n/a