How to send a trace as (x, y) pairs?

I’m excited to use plotly in constrained environments like ESP-32 boards!

I’m facing an issue with sending a large array of data read from a file on an SD card. I see a typical use-case in JS tutorial:

var trace1 = {
    x:['2020-10-04', '2021-11-04', '2023-12-04'],
    y: [90, 40, 60],
    type: 'scatter'

var data = [trace1];

var layout = {
    title: 'Scroll and Zoom',
    showlegend: false

Plotly.newPlot('myDiv', data, layout, {scrollZoom: true});

Sending all Xs and then all Ys will require reading the file twice: for Xs and Ys respectively. Can’t we send a trace as (x, y) pairs?