Is it somehow harmful for a laptop to be shut down and started up several times a day?

Is it somehow harmful for a laptop to be shut down and started up several times a day?

Only if you don't turn it off properly, so tap on the top instead of the windows window at the bottom left

Where did you get it from, whether you shut down using a button or Windows makes no difference…

No. The main things that are harmful to a laptop are heat and dust.

Portable devices are designed for this.

That is not an issue. Of course, every write / read access to the hard disk, regardless of whether it is an ssd or hard disk, is a burden and powering up and down generates write and read access, but leaving it on for the long term is just as important…

I would say that turning a device up or down is just as harmful to a laptop as turning a lamp on or off or starting or stopping a car.

No, not more harmful than working with it.

How do I know: my own experience

Of course, everyone has read / write access to the hard disk, regardless of whether it is an ssd or hard disk […]

Small correction:

With an SSD, reading doesn't bother at all.
The memory cell is only loaded when writing.
And if you leave the SSD without power for a long time, data can be lost.

And since Windows reads more than writes at startup, an SSD is of course more durable than an HDD.
Whether that makes any difference in how most private individuals use it - probably not.