
There’s a lot of isekai anime out there and plenty more coming down the pipeline every new anime season. It’s an anime subgenre that has evolved into its own distinct category like the mecha, harem, and magical girl. It’s anyone’s guess as to why a lot of isekai anime are being produced right now, but I think it's publishers wanting to take advantage of all the content from websites like Shosetsuka ni Naro. Despite this, I also think there’s a small feeling of people wanting to escape our current world and be transported to a fantastical one.
I’ll wholeheartedly admit that watching isekai anime is like eating junk food. They’re not quite “turn off your brain” shows and more “this gives me comfort and I want to enjoy the ride” type of media that’s probably bad for you.
What all isekai anime have in common are the ways in which it transfers its characters to a new world. Here are some of the most common methods:
One way of having the anime protagonist move to another world is to have them die in their previous life and be reincarnated into a new one. Reincarnation is a widely used trope that basically kickstarts a story in the beginning. Although it’s pretty much a cliche for anime storytelling at this point, what interests me about reincarnation isekai stories are the ways it kills off a protagonist in their previous world.
The prime suspect in any isekai death are vehicles, whether it’s through good ol’ Truck-kun, a high-speed subway train, or a speeding car. For example, Rudeus Greyrat from Mushoku Tensei gets killed by a speeding truck in his past life in a failed attempt to save some high school students. Afterwards, he’s reborn as an infant in a fantasy world and his memories intact thanks to a god and begins his life anew.

Tanya Degurechaff (of Saga of Tanya the Evil) was also the victim of an unfortunate vehicular death. In her past life, she was a ruthless Japanese salaryman who feared no god that would interfere with his life. That is, until a disgruntled colleague pushed him off a subway platform into an incoming train, resulting in his death and being forcibly reincarnated into a young lady.

Another way that protagonists are reincarnated is when they’re subject to an incurable nameless disease that saps their ability to move and leaves them bedridden. A deity will often take pity on them and reincarnate them in a healthier body in their next life.
Other ways of reincarnation that I often find in some anime include being stabbed by a knife, shot in the head, pushed off a building, or caught in an unfortunate explosion. Heck, even a god may accidentally kill a main character in the beginning.
There was a recent anime that aired called My Ribdiculous Reincarnation, which is a meta comedy that parodies a lot of the ways isekai stories reincarnate their heroes into other worlds. In the series, the unnamed protagonist takes things a step further when he is killed directly by an incoming meteor that only killed him. As a method of reincarnation, that is certainly an out-of-the-box way of going out.

Isekai shows also bring their protagonists to other worlds by introducing a mechanism to forcibly transport them without killing them. Sometimes you have cases like Subaru Natsuki in Re:Zero, where he's suddenly whisked away into an unknown world after coming back from a convenience store and condemned to a looping life or death scenario.
More commonly, it's magic circles or runes casted by advanced magicians that are used to transport unsuspecting people from Japan to their kingdom in a faraway universe. This is done in order to have them accomplish a great feat like fighting a demon lord and their army. The Rising of the Shield Hero and Arifureta are just some of the shows that have done this.

Of course, sometimes specific individuals are weeded out for displaying a skill that’s deemed worthless. In which case, the protagonist often pivots and lives the life they want without restraint or responsibilities. Besides Arifureta, shows like Campfire Cooking in Another World and Failure Frame have main characters that don’t have to save the world and use the skills that they’ve been given to survive.
It’s safe to say that being transported in this way is a far more acceptable way to travel to another world instead of having to reincarnate.
If reincarnation or being surrounded by magic runes aren't the right way for you to get transported to another world, then maybe having the other world come to you will work better. Reverse isekai anime series like Restaurant to Another World or I Got a Cheat Skill in Another World and Became Unrivaled in the Real World, Too often feature this transportation method.

A magical gate or doorway to another world is so much easier to deal with than dying or being forced into a magic circle in my honest opinion. Doors and gates allow for main characters to easily travel to another world without having to leave their old one and vice versa. Anime like GATE are unique in that they demonstrated how modern military tools would fare against swords, sorcery, and monsters. It also showed the contrast between a modern and feudal world and how its inhabitants react to one another.

Whatever method of transportation you choose to go to another world with, just know which one is the right choice for you for whatever point of life you’re at.