IMO - Sail boat captain in OP video was solely [legally] at fault for coming too close to collision circumstances.
RULE 2
Responsibility
(a) Nothing in these Rules shall exonerate any vessel, or the owner,
master or crew thereof, from the consequences of any neglect to comply with these Rules or of the neglect of any precaution which may be required by the ordinary practice of seamen, or by the special circumstances of the case.
(b) In construing and complying with these Rules due regard shall be had
to all dangers of navigation and collision and to any special circumstances,
including the limitations of the vessels involved, which may make a
departure from these Rules necessary to avoid immediate danger.
—INTERNATIONAL—
Steering and Sailing Rules
RULE 9
Narrow Channels
(a) A vessel proceeding along the course of a narrow channel or fairway
shall keep as near to the outer limit of the channel or fairway which lies on
her starboard side as is safe and practicable.
(b) A vessel of less than 20 meters in length or a sailing vessel shall not
impede the passage of a vessel which can safely navigate only within a
narrow channel or fairway.
(c) A vessel engaged in fishing shall not impede the passage of any other
vessel navigating within a narrow channel or fairway.
(d) A vessel shall not cross a narrow channel or fairway if such crossing
impedes the passage of a vessel which can safely navigate only within such
channel or fairway. The latter vessel may use the sound signal prescribed in
Rule 34(d) if in doubt as to the intention of the crossing vessel.
(e)
(i) In a narrow channel or fairway when overtaking can take place only
if the vessel to be overtaken has to take action to permit safe passing,
the vessel intending to overtake shall indicate her intention by sounding
the appropriate signal prescribed in Rule 34(c)(i). The vessel to be
overtaken shall, if in agreement, sound the appropriate signal
prescribed in Rule 34(c)(ii) and take steps to permit safe passing. If in
doubt she may sound the signals prescribed in Rule 34(d).
(ii) This Rule does not relieve the overtaking vessel of her obligation
under Rule 13.
(f) A vessel nearing a bend or an area of a narrow channel or fairway
where other vessels may be obscured by an intervening obstruction shall
navigate with particular alertness and caution and shall sound the
appropriate signal prescribed in Rule 34(e).
(g) Any vessel shall, if the circumstances of the case admit, avoid
anchoring in a narrow channel.
—INLAND—
Steering and Sailing Rules
RULE 9
Narrow Channels
(a)
(i) A vessel proceeding along the course of a narrow channel or fairway
shall keep as near to the outer limit of the channel or fairway which lies
on her starboard side as is safe and practicable.
(ii) Notwithstanding paragraph (a)(i) and Rule 14(a), a power-driven
vessel operating in narrow channels or fairways on the Great Lakes,
Western Rivers, or waters specified by the Secretary, and proceeding
downbound with a following current shall have the right-of-way over an
upbound vessel, shall propose the manner and place of passage, and
shall initiate the maneuvering signals prescribed by Rule 34(a)(i), as
appropriate. The vessel proceeding upbound against the current shall
hold as necessary to permit safe passing.
(b) A vessel of less than 20 meters in length or a sailing vessel shall not
impede the passage of a vessel that can safely navigate only within a
narrow channel or fairway.
(c) A vessel engaged in fishing shall not impede the passage of any other
vessel navigating within a narrow channel or fairway.
(d) A vessel shall not cross a narrow channel or fairway if such crossing
impedes the passage of a vessel which can safely navigate only within that
channel or fairway. The latter vessel shall use the danger signal prescribed
in Rule 34(d) if in doubt as to the intention of the crossing vessel.
(e)
(i) In a narrow channel or fairway when overtaking, the power-driven
vessel intending to overtake another power-driven vessel shall indicate
her intention by sounding the appropriate signal prescribed in Rule
34(c) and take steps to permit safe passing. The power-driven vessel
being overtaken, if in agreement, shall sound the same signal and may,
if specifically agreed to take steps to permit safe passing. If in doubt
she shall sound the danger signal prescribed in Rule 34(d).
(ii) This Rule does not relieve the overtaking vessel of her obligation
under Rule 13.
(f) A vessel nearing a bend or an area of a narrow channel or fairway
where other vessels may be obscured by an intervening obstruction shall navigate with particular alertness and caution and shall sound the
appropriate signal prescribed in Rule 34(e).
(g) Every vessel shall, if the circumstances of the case admit, avoid
anchoring in a narrow channel.