I agree with you and do consider the default l glyph to be a poor choice, insufficiently distinct from 1. Fortunately, the Code variant of the font goes for a curved tail on l, so that it’s sufficiently distinct.

(However, if you try to enable both the Code and Poly features—Poly meaning “don’t be a true monospace, make characters like l and i a little narrower and characters like m a little wider”—you end up with a slightly narrower flat-bottomed l glyph, rather than a curved tail. See this, for example, in https://chrismorgan.info/blog/make-and-git-diff-test-harness..., which is set in Code + Poly. Disable the `code { font-feature-settings: "ss01" 1, "ss02" }` CSS rule to see the effect of removing Poly—you get the curved tail l glyph back again. I’ve been meaning to sort out a better glyph for the combination, but I haven’t gotten round to it yet, because it’s annoyingly difficult to actually do that sort of thing.)

As mentioned in [1], Triplicate includes a Code variant which disambiguates l and 1, and O and 0, and makes other tweaks for better legibility.

[1] https://practicaltypography.com/triplicate.html

Triplicate has code-specific variants, including a curved lowercase L.