Home networking: Do I need a patch panel, or just connectors?

Solution 1:

Is it possible that that answer is mistaken?

That answer is based on a commercial/industrial standard.
You're asking the wrong question.
You probably want to know how such standards apply to your situation.

Will it be OK to attach connectors to the cat cables, and connect them straight to the switch?

Contrary to one comment, there are 8P8C (aka RJ-45) plugs for solid as well as stranded wire.
(BTW "solid strand cable" as used in at least two comments is an oxymoron. A UTP cable will use either solid wire/conductors or stranded wire/conductors.)

Assuming that the in-wall cable has solid wire, this cable is stiffer than patch cable, which is typically made with stranded wire.
There is no ban or rule that you cannot have a patch cable made from solid wire (e.g. I've made and use several). It's simply not recommended because people tend to be careless and mishandle the (fragile copper) cables as if they were like string or rope.

From a FAQ:

Many misguided IT associates will insist that you must make patch cables from Stranded material, but as usual this just is not true.

If you choose to terminate the in-wall cable with plugs, be sure to use the proper connectors (there are plugs rated for only solid, only stranded, and either stranded/solid wire).
But if these cables are going to be subjected to much flexing (during the modifications and longterm), then it's a bad idea.