This discussion is mostly addressed to Senior and Hero members but anyone can take part.
Most of the Sr and Hero members who comment in Altcoin Discussion are hardcore spammers who have no technical knowledge in cryptocurrency. They just post for filling up their min post count. Hence you won't receive any good replies.
1) top 10 Altcoins with MAX TPS
EOS (10000 max)
NEM (4000)
XRP (1500)
NANO (7000)
NEO (100000 by 2020 with trinity)
OmiseGO (1 million after the plasma implementation)
2) Is it possible to reach 10M TPS in 2018?
I don't think so it can be reached. TPS is based on tx size, block time and block size. If they are high it can be done. But at the moment, it is quite impossible.
3) Is it necessary to have so many TPS?
Not necessarily I think so. There are just a handful of people using cryptocurrency. If crypto becomes mainstream and the world adapts crypto, such a transaction would be required.
4) Do we have a real application now? (do we have a real tasks/applications which require so many TPS)
As I have said above, if the crypto is adapted mainstream we need such high TPS coins.
5) What number of TPS is enought in 2018?
I can't comment on that.