That being said, this is about GUI. No reason not to do as much native processing as your heart desires outside of your GUI layer.
DAW can use pretty much all of system resources (RAM, CPU, disk IO) during playback. If any other thread steals CPU for for too long during playback, like GC of an UI thread, this can introduce audio clicks/pops.
Video conferencing app has tons of network latency which helps to hide other latencies. That kind of latency would be unacceptable in a DAW. Video conferencing app also doesn't starve system of resources like DAW can, so it's UI can be more resource-intensive.
How much? As GP said, > 5ms is instant disqualification. And that is for your whole app, not just the effects pipeline.
GP is right, go use a DAW in a serious setting for a while to build up an intuition of the needs of these users.
I suspect that existing web-as-native-GUI frameworks make presumptions about threading that won't work where a realtime audio callback thread piping data to other audio processing threads and back is the real show, and where the GUI may need things like updated zoom levels dirtying many waveform drawings at once requiring recalculation of peak values in viewable windows to draw the little lines that make the waveform, among other things that may make simple partitioning of systems more challenging...
You're not running 20 different tracks with compression, reverb, chorus, delay + send/return tracks + sub mixes in your app. Your app has absolutely nothing to do with a DAW. You're not taking MIDI input or running virtual instruments either. Try to do that in a browser with a latency < 10ms like Cubase or Logic and see how it goes.
Again, your product has absolutely nothing to do with a DAW and its constraints, so don't try to claim it's an achievement of some sort.
Latency in a DAW isn't just at a premium, it's configurable and needs to be reported and compensated for. That means if any audio processing adds latency, all other processing units must compensate with their own internal (or external) delays to avoid the signal going out of phase.
Apart from that, I don't see how any of this is relevant to how you build the GUI for a DAW.
Download pirated copies of protools and melodyne, and a bunch of virtual instrument libraries from torrents. Download a midi file for a song you like, dump it into protools. Record yourself singing, right on the PC or headset mic - no need to hit the right notes. Dump the voice instrument and your voice recording into Melodyne and drag the voice to match the notes on the voalc tone track. Now set up a link from your Melodyne track into a protools track.
Then go wild, play around, apply filters, do fun stuff. You might get stuck in the fun for a week and it'll keep you awake late.
Once you're done, think about doing all that on a web page or a web page pretending to be a local app. Then reread your comment.
Oh by the way, you will need to install a new raw driver for your soundcard. You see, something like a 5ms audio latency you get from you normal windows sound driver, is too slow. Give some thought on how slow doing anything in JS is going to be, if a native hardware driver is too slow.