Examples based on expected environement generating visuals from / presenting visuals:

a) interactive [2i] & [2iii] / non-interactive

b) generating data for visuals via: sketches by hand[0], gui/command line[1], via database/spreadsheet/ide[2]

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[0] i) : https://www.skillshare.com/en/blog/how-to-digitize-a-sketch-...

   ii) : https://towardsdatascience.com/how-to-convert-any-text-into-a-graph-of-concepts-110844f22a1a

  iii) : https://zapier.com/blog/best-wireframe-tools/

[1] i) overleaf : https://www.overleaf.com/

   ii) tiz and pgf packages : https://tikz.dev/ / https://texample.net/tikz/examples/area/physics/

  iii) ggplot : https://ggplot2.tidyverse.org/

   iv) gnuplot : http://gnuplot.info/

[2] i) jupyter / jupyterlab: https://jupyter.org/

   ii) impress : https://wiki.openoffice.org/wiki/Documentation/OOo3_User_Guides/Impress_Guide/Introducing_Impress

  iii) graphana : https://medium.com/analytics-vidhya/grafana-with-postgresql-data-visualization-with-open-source-tool-36f5150fa290

Walk through of various tools a physics class instructor used per different presenation requirements. https://opensource.com/article/20/1/teach-physics-open-sourc...

Online web based (no install mess):

Mathcha editor : https://www.mathcha.io/ can cut/paste tiz examples to use as starting template(s)

Asmptote : https://asymptote.sourceforge.io/

WolframAlpha : https://www.wolframalpha.com/input/?i=plot+2x%2B3y-5z%3D7

GeoGebra : https://www.geogebra.org/classic/3d

CPM 3D Plotter : https://technology.cpm.org/general/3dgraph/

Additional context: for a flavor of what I have in mind, you can glance at the wiki page for vector spaces [0]. E.g. [1].

[0]: https://en.wikipedia.org/wiki/Vector_space

[1]: https://en.wikipedia.org/wiki/Vector_space#/media/File:Deter...

https://d2lang.com/

Are you asking about the technology to build diagram on web? or what tools to use for creating diagrams?

Because SVG and canvas are technologies, not tools. You then said your intention is to explain technical topics?