It is a commonly known issue of the current Node-RED line chart. As @hotNipi mentioned, the line chart was based on the version v2.xx of Chart.js, which is extremely inefficient. It struggles when displaying slightly fast incoming data (say more than 10 points/second).
Chart.js since 3.0 is much faster and efficient. It would be great if line chart could use Chart.js 3.0 or above.
Alternatively, thanks to @hotNipi and Christian-Me, who have provided ways to use uPlot.
Chirstian-Me started working on a uPlot node and you can see discussions here:
Unfortunately, there are still bugs in the node.
