Tailscale on macOS causing extreme lag spikes

### What is the issue?

For the past few weeks, I have been experiencing incredibly annoying lag spikes when Tailscale is running. It seems to happen regardless of how traffic is routed. It occurs with and without an exit node, it occurs when connecting to a LAN resource, and it occurs when connecting to another device over Tailscale. These lag spikes are significant enough that I can't use my computer when they're happening. They don't *always* happen though. It's just that when they do, Tailscale is enabled.

This has happened across multiple Tailscale versions from the Mac App Store, though I am currently using 1.70.0. It has also happened across many macOS versions, it happened on stable 14.5, and has happened across every beta so far of 15.0 and 15.1.

I have yet to try reinstalling solely because I don't want to lose my Tailnet IP on this MacBook since I remember it by now.

### Steps to reproduce

-

### Are there any recent changes that introduced the issue?

-

### OS

macOS

### OS version

macOS 14.5, 15.0, 15.1

### Tailscale version

1.70.0

### Other software

I have Little Snitch installed but the issue occurs with it disabled too.

### Bug report

BUG-b1f16baec17bb8e258976d39ab6c0cc7e6272d92a629e3413650776c2d8b3c68-20240731214930Z-15bdb24fba4db333