Warning: Lighthouse issues a warning when the page's <body> element has more than ~800 nodes (elements).
Error: Lighthouse reports an error when the <body> element has more than ~1,400 nodes.
Other Related Lighthouse Warnings Lighthouse also flags two other related issues, which often contribute to a large DOM:
Maximum DOM Depth: It warns if your DOM tree has a nesting depth greater than 32 levels.
Maximum Child Elements: It warns if any single parent element has more than 60 direct children.
The general recommendation for optimal performance is to keep your page's total DOM node count below 1,500.
source: https://web.dev/articles/dom-size-and-interactivity
These are "NODES", not even components as you say...
You don't have this problem with UI libraries because all users will run the same library.
Warning: Lighthouse issues a warning when the page's <body> element has more than ~800 nodes (elements).
Error: Lighthouse reports an error when the <body> element has more than ~1,400 nodes.
Other Related Lighthouse Warnings Lighthouse also flags two other related issues, which often contribute to a large DOM:
Maximum DOM Depth: It warns if your DOM tree has a nesting depth greater than 32 levels.
Maximum Child Elements: It warns if any single parent element has more than 60 direct children.
The general recommendation for optimal performance is to keep your page's total DOM node count below 1,500.
source: https://web.dev/articles/dom-size-and-interactivity
These are "NODES", not even components as you say...