even when the name of SIM card holder and bank account holder was not matching, you could withdraw 50,000 per day. It's so for a while. It's all to confirm with international KYC rules, like any other country. Those few, who are affected need to submit residency certificates or similar and show proof that they legally stay in Thailand on a longer visa, same like any other country. Those, who are impacted, should not have been able to open a bank account in the first place and never updated their details. For some nations, new sanction rules kicked in and restricted further the ownership and transfer of funds from bank accounts outside their home country. Very much standard everywhere. For those, who know all and claim it is all BS and against foreigners, might consider relocating to their home country and living free again.
apply for a retirement visa with annual extensions or go for the wealthy retiree LTV which gives you 10 years without the need to renew/extend annually. Most go for the annual extended retirement visa. Keep in mind both visas need proof of a substantial amount of financial assets in a Thai bank account, investment or annual income.
No, they only want to test if you are really a couple and if your wife knows your details like foreign address. There are too many foreigners married in sham marriages, where the 'wife' got paid to pop up when needed, but has no or little relationship to the foreigner. Thailand is full of such arrangements to allow foreigners to open bank accounts and to do all kinds of things you do not want to know. Hence, the personal check with your wife. Nothing stupid about and part of the KYC process.
New regulations came in for KYC verification. Hence they want to see your phone, you use for the banking application is under your name and address. Once proofed you can change the limit in the application.
Except for the visa question, my advice would be to rethink to settle down in Bangkok. As exciting it might be at a first visit, it is not necessarily the greatest and most convenient place to retire, when there are so many other great places to start a new life with new friends.