Why do circuit simulators like LTSpice prefer current sources instead of voltage sources?
That's because LTspice uses the modified nodal analysis, where currents are analyzed, together with conductances &amp; co. Mike Engelhardt, the author of LTspice, said repeatedly that voltage sources, which have (machine) zero internal resistance, pose problems in the matrix solver due to the inversion of this zero resistance. That's not to say voltage sources are prohibited, just that current sources will be superior in terms of convergence.
What is learned in school and how a solver in implemented in software, can be two very different things. And what you're quoting there is not part of the official help, but an addendum from a very knowledgeable member of the LTspice group. But you can read more straight from Mike, himself, from this link.