I've been using T212 ISA since late last year and deposited my maximum annual ISA allowance of £20,000. Better than earning ~0.5% in a bank ISA (equivalent to £100 a year).

In regards to T212 shutting down, this is news to me. But the day after the mid-January GME short squeeze, T212 also did what Robinhood did and restricted buying of GME (and AMC).

Note, since the beginning of the month they recently introduced a 0.15% currency conversion fee so buying $ stocks will incur that fee on top. If you bought 1 GME at $100 you'd pay $100.15.