@Doug ********
I'm Canadian, they still provide the letter of income. You have to go there (Canadian embassy/consulate) with documentation (ie. Assessment letter from Canada revenue, which can be downloaded from their CRA website) and/or one page with company letterhead showing your yearly private pension income.
You then sign an affidavit for the embassy/consulate, after which if they are satisfied that your documentation is legitimate, they write you the letter for Thai immigration.
But sure what the real issue is with the embassies that stopped providing the letters, but it's not on the Thai side (the immigration officer I dealt with, through my local agent, said they prefer the letters and in fact suggested I switch from my marriage visa to retirement visa as that would make the annual renewal a near formality with a letter of income from the consulate ... No bank statements needed.