You'll end up almost exclusively with Chaos rules lovers — you, Alex, Vasya, and a few more players from among your old acquaintances who don't play in modern Tournaments.
And among those who mastered Heroes on Bay and 8mm6, for some reason there are very few opponents of one-way portals. Which is understandable — on 8mm6 a one-way portal is a source of sharp imbalance and often a completely trashed game, simply because there's usually only one maximum and it's right at the exit to the center. And whoever gets it falls significantly behind in scouting tempo and map clearing.
On LM and XM they might bring something interesting, I won't judge, I haven't tried it myself. But the prospect of hitting a dead end with the need to spend a week searching for an entrance deep in the wilderness and dragging a chain of 3-5 heroes there personally does not excite me at all.
The times when games lasted 5-7 weeks and you could skip a week and then get back on track are gone. Now the tempo is quite harsh — if you don't start breaking Dragon Utopia in the beginning of week 3 or you're still without control by the beginning of week 4, be prepared to sign your surrender.
And an awkwardly placed one-way portal can easily throw development back by 3-6 days.
Just that 4x portals made one-way portals imba. I remember even earlier on Bay we fought against 4x portals in TE as a game-balancing feature, and here it's practically the same thing and it's already considered normal.
Here, the access is still to the same 2 zones, often with 2 of the 4 branches in the wilderness. A bit more free money, but otherwise roughly the same thing.
And regarding a one-way portal appearing at respawn, well, there are restarts for that, for example.
If one-way portals on XM were only in the center, where there are plenty of directions without them, they would be playable. But those pests tend to stick themselves in a strategic direction — in the zone for exiting to the center.
So playing with one-way portals by mutual consent is possible, but making it a rule standard means infringing on the interests of those who can't stand them (I think there are quite a few such people).